Fuel additive formulation and method of using same

ABSTRACT

An improved fuel additive formulation, method of use, and method of producing the fuel formulation are described. The improved fuel additive of the present invention comprises a mixture of nitroparaffins (comprising nitromethane, nitroethane, and nitropropane), and a combination of modified commercially available ester oil and/or a solubilizing agent, and/or toluene. The ratio of ester oil and/or solubilizing agent and/or toluence to nitroparaffin is preferably less than 20 volume percent, with nitroparaffins comprising the balance of the additive. A method of preparing and using the additive formulation is also provided.

FIELD OF THE INVENTION

[0001] The present invention relates to an improved fuel additiveformulation for internal combustion engines, and method of making andusing the same. The fuel additive of the present invention provides animproved motor fuel, particularly for automobiles. The formulation ofthe present invention is useful in either gasoline- or diesel-fueledengines, and in automobiles, trucks, and various other engineapplications. In a preferred embodiment, the invention is an additiveformulation, and method of making and using the formulation, to reduceemissions, improve performance and environmental health and safety, andreduce the risks of toxic substances associated with motor fuels.

BACKGROUND OF THE INVENTION

[0002] For some time, various companies and persons have worked toimprove the performance and reduce the adverse environmental effects ofinternal combustion engines. As the increased use of automobiles in theUnited States has offset reductions in auto emissions, legislators,regulators, the petroleum and automobile industries and various othergroups have sought new ways to address air pollution from cars. As partof that effort, these groups have increasingly focused on modificationof fuels and fuel additives. Perhaps the best known fuel modificationrelating to air pollution control is the elimination of lead, used as anantiknock compound, from gasoline.

[0003] The 1990 amendments to the Clean Air Act contain a new fuelsprogram, including a reformulated gasoline program to reduce emissionsof toxic air pollutants and emissions that cause summer ozone pollution,and an oxygenated gasoline program to reduce carbon monoxide emissionsin areas where carbon monoxide is a problem in winter. Environmentalagencies, such as the United States Environmental Protection Agency(EPA) and the California Air Resources Board (CARB), have promulgatedvarious regulations compelling many fuel modification efforts. Acoalition of automobile manufacturers and oil companies has extensivelyreviewed the technology for improving fuel formulations and producedwhat has been referred to as the “Auto/Oil” study. The data from theAuto/Oil study has formed the basis for some regulatory approaches, suchas CARB's matrix of acceptable gasoline formulations.

[0004] With respect to the oxygenated gasoline program, the mostcommonly used oxygenates are ethanol, made from biomass (usually grainor corn in the United States), and methyl tertiary butyl ether (MTBE),made from methanol that is usually made from natural gas. Oxygenatessuch as ethanol and MTBE increase a fuel's octane rating, a measure ofits tendency to resist engine knock. In addition, MTBE mixes well withgasoline and is easily transported through the existing gasolinepipeline distribution network. See, American Petroleum Institutewebsite: Issues and Research Papers (http://www.api.org/newsroom.cgi)“Questions About Ethanol” and “MTBE Questions and Answers”; and“Achieving Clean Air and Water: The Report of the Blue Ribbon Panel onOxygenates in Gasoline” which are incorporated herein by reference.

[0005] Reformulated gasoline has been blended to reduce both exhaust andevaporative air pollution, and to reduce the photochemical reactivity ofthe emissions that are produced. Reformulated gasoline is certified bythe Administrator of the EPA and must include at least two percent (2%)oxygenate by weight (the so-called “oxygen mandate”). Ethanol and MTBEare both used in making reformulated gasoline.

[0006] Both ethanol (as well as other alcohol-based fuels) and MTBE havesignificant drawbacks. Ethanol-based fuel formulations have failed todeliver the desired combination of increased performance, reducedemissions, and environmental safety. They do not perform substantiallybetter than straight-run gasoline and increase the cost of the fuel.

[0007] Adding either ethanol or MTBE to gasoline dilutes the energycontent of the fuel. Ethanol has a lower energy content than MTBE, whichin turn has a lower energy content man straight-run gasoline. Ethanolhas only about 67% the energy content of the same volume of gasoline andit has only about 81% of the energy content of an equivalent volume ofMTBE. Thus, more fuel is required to travel the same distance, resultingin higher fuel costs and lower fuel economy. In addition, the volatilityof the gasoline that is added to an ethanol/gasoline blend must befurther reduced in order to offset the increased volatility of thealcohol in the blend.

[0008] Ethanol has not proven cost effective, and is subject torestricted supply. Because of supply limitations, distribution problems,and its dependence on agricultural conditions, ethanol is expensive. TheAmerican Petroleum Institute reports that, in 1999, ethanol was abouttwice the cost of an energy equivalent amount of gasoline. The politicsof agriculture also effect ethanol supply and price.

[0009] Ethanol also has a much greater affinity for water than dopetroleum products. It cannot be shipped in petroleum pipelines, whichinvariably contain residual amounts of water. Instead, ethanol istypically transported by truck, or manufactured where gasoline is made.Ethanol is also corrosive. In addition, at higher concentrations, theengine must be modified to use an ethanol blend.

[0010] Ethanol has other drawbacks as well. Ethanol has a high vaporpressure relative to straight-run gasoline. Its high vapor pressureincreases fuel evaporation at temperatures above 130° Fahrenheit, whichleads to increases in volatile organic compound (VOC) emissions. EPA hasconcluded that VOC emissions would increase significantly with ethanolblends. See, Reformulated Gasoline Final Rule, 59 Fed. Reg. 7716, 7719(1994).

[0011] Finally, although much research has focused on the health effectsof ethanol as a beverage, little research has addressed ethanol's use asa fuel additive. Nor has ethanol been evaluated fully from thestandpoint of its environmental fate and exposure potential.

[0012] MTBE has its share of drawbacks as well. MTBE was first added togasoline to boost the octane rating. In line with the 1990 Clean Air Actamendments, MTBE was added in even larger amounts as an oxygenate toreduce air pollution. Unfortunately, MTBE is now showing up as acontaminant in groundwater throughout the United States as a result ofreleases (i.e., leaking underground gasoline storage tanks, accidentalspillage, leakage in transport, automobile accidents resulting in fuelreleases, etc.).

[0013] MTBE is particularly problematic as a groundwater contaminantbecause it is soluble in water. It is highly mobile, does not cling tosoil particles, and does not decay readily. MTBE has been used as anoctane enhancer for about twenty years. The environmental and healthrisks posed by MTBE, therefore, parallel those of gasoline. Some sourcesestimate that 65% of all leaking underground fuel storage tank sitesinvolve releases of MTBE. It is estimated that MTBE may be contaminatingas many as 9,000 community water supplies in 31 states. A University ofCalifornia study showed that MTBE has affected at least 10,000groundwater sites in the State of California alone. The full extent ofthe problem may not be known for another ten years. See, “MTBE, to WhatExtent Will Past Releases Contaminate Community Water Supply Wells?,”ENVIRONMENTAL SCIENCE AND TECHNOLOGY, at 2-9 (May 1, 2000), which isincorporated herein by reference.

[0014] EPA also has determined that MTBE is carcinogenic, at least wheninhaled. Other unwelcome environmental characteristics are its foulsmell and taste, even at very low concentrations (parts per billion).Because of these drawbacks, the U.S. Government is considering banningMTBE as a gasoline additive. In September 1999, the EPA recommended thatMTBE use be curtailed or phased out. Several states are planning to haltor reduce MTBE use. California plans to phase it out by 2002, and Mainealready has the EPA's permission to quit using MTBE if it can find otherways of meeting air quality standards. The EPA also has approved NewJersey's request to stop using MTBE in gasoline during the winter.

[0015] The environmental threat from MTBE may be even greater than thatfrom an equivalent volume of straight-run gasoline. The constituents ofgasoline considered most dangerous are the aromatic hydrocarbons:benzene, toluene, ethylbenzene, and xylene (collectively, “BTEX”). TheBTEX aromatic hydrocarbons have the lowest acceptable drinking watercontamination limits. Both ethanol and MTBE enhance the environmentalrisks posed by the BTEX compounds, apart from their own toxicity.Ethanol and MTBE act as a co-solvent for BTEX compounds in gasoline. Asa result, the BTEX plume from a source of gasoline contaminationcontaining ethanol and/or MTBE travels farther and faster than one thatdoes not contain either oxygenate.

[0016] The BTEX aromatic compounds have relatively lower solubility inwater than MTBE. BTEX compounds tend to biodegrade in situ when theyleak into the soil and ground water. This provides at least some naturalattenuation. Relative to the BTEX compounds, however, MTBE biodegradesat a significantly lower rate, by at least one order of magnitude, orten times more slowly. Some sources estimate that the time required forMTBE to degrade to less than a few percent of the original contaminantlevel is about ten years.

[0017] Other initiatives have involved efforts to formulate a cleanerburning—reformulated—gasoline (RFG). For example, Union Oil Company ofCalifornia (UNOCAL) has secured a number of U.S. patents that covervarious formulations of RFG. Jessup, et al., U.S. Pat. No. 5,288,393,for Gasoline Fuel (Feb. 22, 1994); Jessup, et al., U.S. Pat. No.5,593,567, for Gasoline Fuel (Jan. 14, 1997); Jessup, et al., U.S. Pat.No. 5,653,866, for Gasoline Fuel (Aug. 5, 1997); Jessup, et al., U.S.Pat. No. 5,837,126 for Gasoline Fuel, (Nov. 17, 1998); Jessup, et al.,U.S. Pat. No. 6,030,521 for Gasoline Fuel (Feb. 29, 2000). The UNOCALpatents specify various end points in the blending of gasoline, andpurport to reduce emissions of selected contaminants: Carbon monoxide(CO); Nitric oxides (NOx); Unburned Hydrocarbons (HC); and otheremissions.

[0018] UNOCAL has already enforced one of its RFG patents. Union OilCompany of California v. Atlantic Richfield, et al., 34 F.Supp.2d 1208(C.D. Cal. 1998); and Union Oil Company of California v. AtlanticRichfield, et al., 34 F.Supp.2d 1222 (C.D. Cal. 1998). The DistrictCourt judgment established a substantial royalty rate (5 ¾ cents pergallon) for UNOCAL's patented RFG formulation. This has increasedsubstantially the cost of motor fuels in the affected markets. Althoughthe judgment has been affirmed on appeal, Union Oil Company ofCalifornia v. Atlantic Richfield, et al., 208 F.3d 989, 54 USPQ2d 1227(Fed. Cir. 2000), and the Supreme Court has denied review.

[0019] Historically, margins in the refining and marketing of motorfuels tend to be narrow, typically less than cents a gallon. AlexiBarrionuevo, “Stumped at the Pump? Look Deep into the Refinery,” WALLSTREET JOURNAL, B1 (May 26, 2000), which is incorporated herein byreference. RFG imposes added costs on refiners. These formulationsincrease the cost of the finished product, relative to straight-rungasoline. Memorandum from Lawrence Kumins, Specialist in Energy Policy,Resources, Science and Industry Division, Library of Congress, toMembers of Congress, “Midwest Gasoline Price Increases (Jun. 16, 2000),which is incorporated herein by reference. UNOCAL's royalty rate of 5¾cents per gallon imposes a substantial additional cost burden on RFG.

[0020] These various problems have impaired the efficacy orcost-effectiveness of each of these various alternatives. Alcohols havenot resolved the performance and emission needs for improved motorfuels. MTBE imposes unacceptable environmental (soil and groundwater)and public health problems. Methyl Teritary Butyl Ether (MTBE), 65Fed.Reg. 16093 (2000) (to be codified at 40 C.F.R. pt. 755) (proposedMar. 24, 2000). Reformulated gasoline has been controversial andexpensive. Accordingly, there remains a substantial and unmet need foran improved gasoline formulation that enhances (or at least does notimpair) performance, while reducing emissions and the environmental andpublic health risks from motor fuels. The present invention satisfiesthose needs.

[0021] The present invention employs a unique combination ofnitroparaffins and ester oil, to enhance the performance of and reduceemissions from internal combustion engines and, in particular,automobiles. Nitroparaffins have been used in prior fuel formulations,for different engine applications, without achieving the results of thepresent invention. For example, nitroparaffins have long been used asfuels and/or fuel additives in model engines, turbine engines, and otherspecialized engines. Nitromethane and nitroethane have been used byhobbyists. Nitroparaffins have also been used extensively in dragracing, and other racing applications, due to their extremely highenergy content.

[0022] The use of nitroparaffins in motor fuels for automobiles,however, has several distinct disadvantages. First, some nitroparaffinsare explosive and, pose substantial hazards. Second, nitroparaffins aresignificantly more expensive than gasoline—so expensive as to precludetheir use in automotive applications. Third, nitroparaffins havegenerally been used in specialized engines that are very different thanautomotive engines. Fourth, the high energy content of nitroparaffinsrequires modification of the engine, and additional care in transport,storage, and handling of both the nitroparaffin and the fuel. Further,in some fuel applications, nitroparaffins have had a tendency to gel.The high cost, and extremely high energy content of nitroparaffins, hasprecluded their use as an automotive fuel. Moreover, the extremevolatility and danger of explosion from nitromethane taught away fromits use as a motor fuel for automobiles.

[0023] Notwithstanding these drawbacks, patents have been issued forfuel formulations containing nitroparaffins. One of these, Michaels,U.S. Pat. No. 3,900,297 for Fuel for Engines (Aug. 19, 1975), describesa fuel formulation for engines comprising nitroparaffin compositions.Michaels notes that nitroparaffin formulations have a tendency topre-ignition in reciprocating internal combustion engines. Moreover,Michaels notes that nitroparaffins are not readily miscible inhydrocarbons.

[0024] Michaels discloses and claims a formulation that is intended toincrease the solubility of nitroparaffins in hydrocarbons. Michaelsclaims that nitroparaffins can be made soluble in gasoline by includinga synthetic ester lubricating oil. Michaels specifies that anycommercially available gasoline, having a boiling point between 140° to400° F. is suitable. Michaels asserts that the inclusion of esterlubricating oil at the levels specified by Michaels “would renderperfectly miscible otherwise immiscible nitroalkane/gasoline blends.”Michaels '297 patent, at Col. 2, 11. 27-28.

[0025] Michaels expressly notes that one of the advantages of includingester lubricating oil in his invention is to provide upper cylinderlubrication: “[i]nclusion of ester lubricant in fuel compositions forreciprocating combustion engines has the further advantage of providinginternal lubrication within the engine, thereby reducing engine wear andimproving engine efficiency.” Michaels, '297 patent at Col. 2, 11.31-35. “Ester lubricants of the type suitable for use in the fuelcompositions of the present [Michaels'] invention include those whichhave found wide use as “synthetic oil” in modern jet engines. Theseinclude the commercially available synthetic lubricating oils metting[sic] Military Specifications MIL-L-7808 and MIL-L-9236 of the estertype. Specific examples of commercially available synthetic oilssuitable for use in the compositions of the present invention includeTexaco SATO No. 7730 Synthetic Aircraft Turbine Oil, Monsanto SkylubeNo. 450 Jet 20 Engine Oil, and Mobil] II Turbine Oil.” Michaels '297patent, at Col. 3, 11. 11-21. Michaels describes the chemicalformulations of various ester oils, Michaels '297 patent, at Col. 3, 11.11 to Col. 6, 11. 42, which discussion is incorporated herein byreference. The ester lubricating oils of the present invention include,without limitation, those described by Michaels in his '297 patent aswell as any other ester oils that may be suitable to achieve the objectsof the present invention.

[0026] Michaels expressly notes that: “[c]ommercially available esteroils of the above description usually contain additives to improve theirperformance as lubricants, which additives do not ordinarily adverselyaffect performance of such oils in my [Michaels'] fuel compositions. Ingeneral, for reasons of ready availability, use of ester oil in the formof commercially available synthetic ester turbine oils is preferred.”Michaels '297 patent, at Col. 4, 11. 44-50. Michaels not only includesthe additives normally found commercially in such ester oils, heexpressly prefers them.

[0027] Among those additives typically included in commerciallyavailable ester oils are flame retardants. These flame retardantsinhibit the combustion of the oil, without impairing the miscibility ofthe nitroparaffins, allowing the ester oil to lubricate the uppercylinder.

[0028] Michaels specifies that: “[t]he ester oil is preferably employedin minimum amount required to provide a homogeneous liquid fuelcompositions [sic]. Use of less than that amount results innon-homogeneous compositions, with concomitant physical separation ofliquid components into layers, and use of excess amounts of ester oil iswasteful and may result in excess carbon deposition within the engine,fouling of sparkplugs and generally unsatisfactory engine operation. Nogeneral rule can be set down fixing precise amounts of ester oilrequired to achieve homogeneity of the compositions, since that amountdepends on variables such as the type of gasoline, nitroalkane and esteroil, as well as the proportions in which gasoline and nitroalkane areincorporated into the composition . . . As a general guide, use of esteroil in proportions of from 1 to 4 parts of ester oil to 8 parts ofnitroalkane will ordinarily provide a homogeneous blend.” Michaels '297patent, at Col. 5, 11. 47 to Col. 6, 11. 2.

[0029] Michaels' only disclosure of making the additive or fuel relatesto how to determine the appropriate amount of ester oil to provide ahomogeneous blend: “the required amounts of ester oil are readilydetermined by simple experimentation of a routine nature, e.g. by firstadding the nitroalkne to the gasoline in desired amount, then adding theester oil in small portions, followed by thorough mixing after eachaddition, until a homogeneous blend is obtained.” Michaels, '297 patent,at Col. 5, 11. 61-66. In contrast, both the process of the presentinvention and the product obtained by the present process, are differentthan Michaels.

[0030] Michaels claims that his invention improves combustionefficiency: “[t]he advantages of using the fuel of the present inventionare found in lower fuel consumption due to high BTU of energy developedresulting in higher horsepower output and cleaner burning, since theadded blends (of nitroalknes and their mixtures) improve combustionefficiency,” Michaels '297 patent at Col. 6, 11. 29-34, in conjunctionwith glow plug engines. Michaels speculates that “[t]he same advantagesmay occur when this fuel is used in other internal combustion engines orjet engines.” Michaels '297 patent, at Col. 6, 11. 34-36. Yet, Michaelsprovides no data to support this conjecture. Nor does Michaels identifyany increase in horsepower or reduction in emissions, apart from highBTU content and higher fuel efficiency of Michaels' fuel.

[0031] Michaels claims a fuel comprising from 5 to 95% (volume) gasolineand 95 to 5% additive. Michaels' additive, in turn, comprises from 10 to90% nitroparaffin and 90 to 10% ester lubricating oil. Michaels claimsthat his fuel is a homogeneous blend of additive and gasoline. Heattributes his results to the ability of the ester lubricating oil tomake the nitroparaffin soluble in gasoline. Michaels' components are ablend and do not react with one another. They are a simple mixture.

[0032] The present inventors are not aware that the formulationdescribed and claimed by Michaels has ever been used as a motor fuel forautomobiles. Although Michaels sold a fuel additive for automobiles, thepresent inventors believe that the additive Michaels sold may have beendifferent than the additive disclosed in Michaels' '297 patent.

[0033] Michaels' fuel comprises 0.5 to 81.5 volume percent nitroalkane.At levels this high, Michaels' formulation teaches strongly away fromautomotive applications. The energy content of the nitroalkanes issimply too high for automotive use. Michaels himself provided examplesof only model engines, turbine, jet engine, and other specializedapplications. Nor would Michaels have been understood by persons ofordinary skill in the art as suggesting a viable automotive fuel. Highnitroalkane levels would likely damage or destroy an automotive engine.

[0034] The cost of Michaels' additive is substantially higher than thecost of gasoline. At a concentration of even 5 volume percent, the costof the finished formulation blended according to Michaels' teachingswould be multiples, if not orders of magnitude, higher than the cost ofan equivalent volume of gasoline. At higher concentrations, whichMichaels teaches may range up to 95 volume percent, the cost isprohibitive. Michaels' fuel is not cost-effective for motor vehicle use.

[0035] Prior to 1985, a similar composition was marketed by anindividual named Moshe Tal, through a corporation named TK-7. Mr. Talsold the formulation as “ULX-15.” From 1985 to March of 1987, Talsupplied a formulation that reportedly was made in accordance with the'297 patent, to a company trading under the name Energex. Energexactively marketed the product throughout the western United States byadvertising it in “outdoor” magazines such as FIELD AND STREAM. Energexprincipals attended various events, such as fishing competitions, whereon at least one occasion they demonstrated the Energex/TK-7 product foruse in fishing boat engines. The Energex/TK-7 formulation enjoyedlimited sales only in a narrow, non-automotive market. Michaels laterasserted that the Energex/TK-7 formulation was covered by his '297patent.

[0036] The present inventors believe that the Energex/TK-7 formulationcomprised the following composition: TABLE 1 “Energex/TK-7” FormulationVolume of Formulation Component (Parts of Total) 2-nitropropane 35-38Nitroethane 3-4 Nitromethane 1-2 Mobil Jet II ™ ½-1   Alcohol (methanolor isopropyl) 1-2 Total: 40½-47  

[0037] In 1986, an individual identifying himself as Michaels contactedEnergex, and claimed that Energex's additive infringed Michaels' '297patent. A principal of Energex, Don Young, met with Michaels in New Yorkin 1986. Young observed some portions of Michaels' preparation of the'297 additive. Although no mixing process is disclosed in the '297patent, Young understood that the preparation of the '297 compositioninvolved a specific mixing procedure. Energex and Michaels entered intoan agreement whereby Energex continued to sell the formulation.

[0038] The present inventors believe that the Energex/TK-7 additive wassold for both gasoline and diesel-fueled outboard motor engines. One ortwo gallons of diesel fuel was added to the diesel formulation. Thepresent inventors are unaware of any performance testing of the Michaelsformulation from this time period (prior to March 1987). In 1987,Energex ran out of money, declared bankruptcy, and stopped selling. TheTK-7 product was not marketed from March of 1987 until about May of1988.

[0039] In May of 1988, Young began selling the product in a slightlymodified form, under the name “PbFree.” PbFree secured product from W.R. Grace, under Michaels' supervision. PbFree sold the formulation as“TGS.” The TGS formulation of the additive as sold by PbFree wassubstantially the same as the Energex/TK-7 formulation: TABLE 2 PbFree“TGS” Formulation (1988 to 1990) Volume of Formulation Component (Partsof Total) 2-nitropropane 35-38 Nitroethane 3-4 Nitromethane 1-2 MobilJet II ™ ½-1   Alcohol (methanol or isopropyl) 1-2 Total: 40½-47  

[0040] Although the present inventors are aware of no performance dataavailable for the Energex/TK-7 formulation that was apparently sold fromprior to 1985 through 1987, performance testing was conducted on thePbFree TGS formulation between 1989 and 1990.

[0041] As a general proposition, motor fuel testing is subject to a highdegree of variability, requiring precisely defined test parameters andcontrols. Gasoline is extremely variable in composition. Control of thefuel is essential to securing statistically significant results fromengine performance testing. Annual Book of ASTM Standards 2000, SectionFive: Petroleum Products, Lubricants, and Fossil Fuels, Volume 05.04,Petroleum Products and Lubricants (V): D 5966—latest; American NationalStandards Institute (ANSI), “Automotive Fuels—Diesel—Requirements andTest Methods”, Publication No. SS-EN 590, and “Automotive Fuels—Unleadedpetrol—Requirements and Test Methods,” Publication No. SS-EN 228;Society of Automotive Engineers (SAE), “Automotive Gasolines,”Publication No. J312199807 (July 1998), which are incorporated herein byreference.

[0042] Different runs of the same formulation under comparableconditions may vary by as much as 5-17%, depending on the emissionvariable being measured. Variability is also inherent in the datacollected in performance testing. Vehicles differ and even the samevehicle varies in performance from day to day. The variability between“nominally identical cars” can be from approximately 10 to 27 percent ofthe mean value, for a repeated number of tests using the same fuel in anumber of similar vehicles. The Effects of Aromatics, MTBE, Olefins andT ₉₀ on Mass Exhaust Emissions from Current and Older Vehicles—TheAuto/Oil Quality Improvement Research Program. Society of AutomobileEngineers (SAE) Technical Paper Series 912322, International Fuels andLubricants Meeting and Exposition, Toronto, Canada (Oct. 7-10, 1991),which is incorporated herein by reference. In repeated testing of thesame vehicles using the same fuel, results may vary from approximately 5to 17% of the mean value (SAE, 1991). Atmospheric conditions, such ashumidity, may also introduce variability. (SAE, 1991).

[0043] The testing of the TGS product between 1989 and 1990 did notsatisfy even these generally accepted requirements for reliability inengine performance testing. Accordingly, the variability of the TGS testdata is expected to be even higher than 5-17%.

[0044] Prelimiary testing of the TGS product was conducted by theUniversity of Nebraska and Cleveland State University in 1989 and 1990.Both were small “pilot” studies. Both researchers recommended moreaggressive tests to validate the initial results. The present inventorsbelieve that such definitive testing was never conducted.

[0045] Professor Ronald Haybron of the Department of Physics of theCleveland State University conducted a preliminary evaluation of the TGSproduct in 1989. He tested one vehicle and used regular (87 octane)unleaded pump gasoline, rather than a standard fuel formulation, asrequired by generally accepted testing standards. Nor were data measuredat the same points (for example, at the same engine speeds). Theselimitations of procedure, small sample size, and lack of adequatecontrol preclude any reliable conclusions being drawn from the ClevelandState study.

[0046] The Cleveland State study tested the additive at a concentrationof 0.1 oz. of additive per gallon of fuel. This is a concentration ofadditive well below the levels specified and claimed in Michaels' '297patent. Michaels discloses an additive concentration of 5 to 95% (6.25oz. to 121.6 oz. per gallon) or more. The Cleveland State test was runoutside that range. Although the results were not statisticallysignificant, Prof. Haybron claimed an improvement in horsepower of 8 to20%, and reduced carbon monoxide output of 8 to 10%, well within thevariability of even a well-controlled study.

[0047] Professor Peter Jenkins, of the University of Nebraska, failed toreplicate these results. The University of Nebraska, MechanicalEngineering Department conducted testing on the “TGS Fuel Additive.” TheNebraska testing evaluated the data at the same engine speeds for eachconcentration of additive. However, pump gas (regular 87 octane) wasalso used instead of a controlled, reference fuel. Only two vehicleswere tested. Although some evaluations showed improvement at higherconcentrations of additive (i.e., at 0.5 oz. per gallon), they showedlittle, if any, difference at the lowest concentrations tested (0.1 oz.per gallon). Although Prof. Jenkins claimed that the testing showed a 10to 14% improvement in fuel consumption, those values are well within thevariability of even a well-controlled study. There was little to noimprovement on other parameters.

[0048] In 1990, PbFree modified the formulation but continued sellingthe additive having the composition identified in Table 3: TABLE 3PbFree Formulation (1990 to 1998) Volume of Formulation Component (Partsof Total) 2-nitropropane 28  Nitroethane 11-15 Nitromethane  6-15 MobilJet II ™ 1 Total: 46-59

[0049] The present inventors believe that PbFree attempted to sell theproduct to leaseway Trucking Company and the Cummins Engines Corporationduring 1991. At that time, the formulation was supplied by W. R. Graceunder Michaels' supervision.

[0050] The present inventors believe that PbFree supplied the product tothe Brigham Young University (BYU), School of Engineering for testing.The product was provided by Michaels. The present inventors understandthat the PbFree composition failed to improve performance or reduceemissions in the BYU tests.

[0051] In 1992, Michaels stopped supplying product to PbFree. Youngattempted to replicate Michaels' formulation from publicly availablesources, such as Michaels '297 patent. Young was unable to replicateMichaels' formulation from the '297 patent alone, yet, based uponYoung's observation of Michaels preparing his additive in 1986, Youngdetermined that a special mixing step was necessary. Young experimentedwith various methods—stirring, rolling the components in a closedbarrel, and “thermoaeration”—and was able to offer an additiveformulation for sale. None of these mixing procedures are disclosed inMichaels' '297 patent.

[0052] Young continued making and selling the formulation identifiedabove as the “PbFree” formulation, until 1998, at which point PbFreeceased operations. The present inventors are aware of no testingregarding the performance of the PbFree formulation during this period.In 1998, Young began selling the additive under the name Envirochem, LLC(“Envirochem”). The Envirochem “EChem” formulation is identified inTable 4: TABLE 4 Envirochem “EChem” Formulation (1998 to 1999) Volume ofFormulation Component (Parts of Total) Nitropropane (1 or 2) 29Nitroethane 10 Nitromethane 10 Toluene 5 Mobil Jet II ™ 1 Total: 55

[0053] In addition to the prior formulations derived from Michaels(namely, the ULX-15, TGS, PbFree, and EChem formulation discussedabove), other inventors have disclosed and claimed additives comprisingnitroparaffins and either toluene and/or ester oil. Many of these priorknown formulations, however, were either for use as a model engine fuelor lubricant. See e.g., Brodhacker, U.S. Pat. No. 2,673,793 for ModelEngine Fuel (Mar. 30, 1954); Hartley, U.S. Pat. No. 5,880,075 forSynthetic Biodegradable Lubricants and Functional Fluids (Mar. 9, 1999);and Tiffany, U.S. Pat. No. 5,942,474 for Two-Cycle Ester Based SyntheticLubricating Oil (Aug. 24, 1999). Two patents of which the presentinventors are aware disclose the use of a nitroparaffin and esteroil/toluene formulation for use as a fuel additive: Gorman, U.S. Pat.No. 4,330,304 for Fuel Additive (May 18, 1982); and Simmons, U.S. Pat.No. 4,073,626 for Hydrocarbon Fuel Additive and Process of ImprovingHydrocarbon Fuel Combustion (Feb. 14, 1978).

[0054] Gorman discloses a mixture of nitroparaffins, including:nitropropane, nitroethane, nitromethane, and others, at 3-65 weightpercent of the additive. Gorman also discloses formulations in whichtoluene is present at a concentration of 74 weight percent, well inexcess of the present invention, along with propylene oxide, tert-butylhydroperoxide, nitropropanes 1 and 2, and acetic anhydride. Gorman, '304Patent, Col. 9, 11. 53.

[0055] Simmons discloses a mixture of one part iron salts of aromaticnitro acid, 10 to 100 parts nitroparaffin, and a solvent, which may betoluene. Simmons does not disclose the use of ester oil. In some ofSimmons' examples, the salt is added directly to the fuel with nosolvent. In at least two of Simmons' examples, the solvent comprisesabout a quarter of the fuel blend, well in excess of the concentrationsof toluene and/or ester oil in the present invention.

[0056] Neither Gorman nor Simmons, nor any of the other known priorformulations, disclose the ranges of nitroparaffins, and ester oiland/or toluene of the present invention, let alone the unique benefitsof the present invention to reduce emissions. Prior known formulationswere made by a different process than the present invention. Many of theprior known formulations are used at higher concentrations in the fuelthan is the present invention. The present invention, however, reducesemissions at lower concentrations of additive. In addition, the presentinvention may be used with a variety of fuels, including: gasoline,gasoline and MTBE, gasoline and ethanol, and gasoline/ethanol/MTBEformulations.

[0057] In January 2000, Envirochem's assets were purchased by FirstStanford Envirochem, Inc., trading as Magnum Environmental Technologies,Inc., the assignee of the present application. The present inventorshave made a diligent effort to study and improve upon the prior knownformulations. As a result of these efforts, the present applicants haveinvented a new formulation, and method of producing and using the same.

[0058] The present inventors began by investigating the EChemformulation. A study conducted by Emission Testing Service (ETS) inJanuary 2000 found that, although the EChem formulation performedcomparable to or slightly worse than both a standard unleaded gasolineand standard gasoline plus 11% MTBE, it reduced carbon monoxideemissions relative to gasoline, reduced NOx emissions relative togasoline plus MTBE, and improved fuel efficiency relative to both.

[0059] The present invention differs in significant respects from theprior known formulations, as well as from alcohol-based (ethanol) andMTBE fuel additives, and performs better than prior known formulations.One embodiment of the present invention is disclosed in Table 5: TABLE 5“MAZ 100” Formulation Volume of Formulation Component (Parts of Total)1-nitropropane 29 Nitroethane 10 Nitromethane 10 Toluene 5 ModifiedEster Oil Lubricant 1 Total: 55

[0060] The present inventors have made a number of specific changes inthe formulation and in the method of preparing the composition of thepresent invention. The present inventors believe that these changesproduce the improvements they have observed.

[0061] Although prior formulations used 2-nitropropane, or a combinationof 1-nitropropane and 2, the present inventors preferably remove2-nitropropane from the formulation. 2-nitropropane is a knowncarcinogen. Its removal improves the material handling safety of theproduct.

[0062] Unlike the prior known formulations, which employed commerciallyavailable ester oils, the present inventors preferably modify the esteroil to remove, or not to introduce, tricresyl phosphate. Tricresylphosphate is a known neurotoxin. In addition, tricresyl phosphate hasflame retardant properties. The present inventors believe that thismodification allows improved performance of the invention in terms ofreduced emissions, at lower concentrations of additive, particularly oncold start up. It also makes the product safer to handle.

[0063] The present inventors preferably add toluene to the formulation.The inventors believe that toluene may emulsify the nitroparaffins into,or make the nitroparaffins more soluble in, gasoline and loweremissions.

[0064] The present inventors preferably lower the amount of ester oil tolevels below most of the known prior additives. This too has been foundto lower emissions.

[0065] The present inventors preferably lower the concentration ofnitromethane. Nitromethane is also a known neurotoxin. Reduction ofnitromethane reduces toxicity and lowers emissions.

[0066] The present invention is preferably employed at a lower overallconcentration in the fuel relative to most prior known formulations.This too lowers emissions and reduces toxicity.

[0067] The present invention improves performance, reduces materialhandling requirements, and lowers environmental and public health andsafety risks, as well as emissions, at concentrations at which priorformulations were either untested, ineffective, or failed to produce theunique combination of benefits of the present invention.

[0068] It has not been reliably established that the prior knownformulations provided any improvement in performance or emissions. Thepresent invention, on the other hand, achieves benefits, at lowconcentrations of additive. Thus, the present invention meets thelong-felt, yet unresolved, need for an environmentally safe, improvedfuel additive. None of the prior formulations of which the presentinventors are aware reduce emissions, particularly on cold start-up.None of the prior known formulations suggest the present invention.

OBJECTS OF THE INVENTION

[0069] It is an object of the present invention to provide a motor fueladditive that provides improved performance at additive concentrationstypical of known additives, and reduced emissions at lowerconcentrations, while avoiding many of the problems associated withprior known additives and motor fuels.

[0070] Another object of the present invention is to provide a motorfuel that exhibits improved performance relative to prior known motorfuels, while avoiding many of the problems associated with prior knownmotor fuels.

[0071] A further object of the present invention is to provide a motorfuel that reduces emissions relative to prior known motor fuels, whileavoiding many of the problems associated with prior known motor fuels.

[0072] Yet another object of the present invention is to provide areplacement, or supplement, for oxygenates, such as ethanol and MTBE.

[0073] Another object of the present invention is to provide areplacement, or supplement, for oxygenates, such as ethanol and MTBE,that reduces emissions.

[0074] A further object of the present invention is to reduce emissionson cold start-up.

[0075] An additional object of the present invention is to provide animproved fuel formulation that reduces total hydrocarbon emissions.

[0076] Yet another object of the present invention is to provide animproved formulation that reduces non-methane hydrocarbon emissions.

[0077] Another object of the present invention is to provide an improvedfuel formulation that reduces carbon monoxide emissions.

[0078] A further object of the present invention is to provide animproved fuel formulation that reduces NO_(x) formation.

[0079] An additional object of the present invention is to provide animproved fuel formulation that reduces ozone formation.

[0080] Yet another object of the present invention is to reduce theformation of precursors to ozone formation.

[0081] Another object of the present invention is to reduce hydrocarbonemissions on cold start up.

[0082] A further object of the present invention is to reduce carbonmonoxide emissions on cold start up.

[0083] An additional object of the present invention is to reduce NOxemissions on cold start up.

[0084] Yet another object of the present invention is to reduce ozoneformation on cold start up.

[0085] Additional objects and advantages of the invention are set forth,in part, in the description which follows and, in part, will be obviousfrom the description or may be learned by practice of the invention. Theobjects and advantages of the invention will be realized in detail bymeans of the instrumentalities and combinations particularly pointed outin the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0086]FIG. 1 is a graph depicting the percent improvement in emissionsof a fuel comprising the additive of the present invention (MAZ 100)relative to Indolene, a standard reference fuel.

[0087]FIG. 2 is a graph depicting the percent improvement in emissionsof a fuel comprising the additive of the present invention (MAZ 100)relative to MTBE.

[0088]FIG. 3 is a graph depicting the percent improvement in emissionsof a fuel comprising the additive of the present invention (MAZ 100)relative to RFG.

[0089]FIG. 4 is a graph depicting the prior art, namely, the percentimprovement in emissions of a fuel comprising MTBE over Indolene, astandard reference fuel.

[0090]FIG. 5 is a graph depicting the prior art, namely, the percentimprovement in emissions of RGF relative to Indolene, a standardreference fuel.

[0091]FIG. 6 is a graph depicting the percent improvement in emissionsof fuels comprising the present invention (MAZ 100), and MTBE and RFG ofthe prior art, each relative to Indolene, a standard reference fuel.

BRIEF SUMMARY OF THE INVENTION

[0092] The present invention comprises an improved fuel additiveformulation and method of making and using the same. As embodied herein,the present invention comprises: an additive formulation for fuels, anda fuel containing the additive, comprising: nitroparaffin; and ester oiland/or a solubilizing agent and/or aromatic hydrocarbon; said fuelresulting in reduced emissions relative to a fuel not containing saidadditive when burned in a boiler, a turbine, or an internal combustionengine.

[0093] In another embodiment, the present invention comprises: anadditive formulation for fuels, or a fuel containing the additive,comprising: a first component, comprising 0 to 99 volume percentnitroparaffin, selected from the group consisting of: 1-nitropropane,2-nitropropane, nitroethane, and nitromethane; a second component,substantially comprising the balance of the additive formulation,selected from the group consisting of: ester oil lubricant, and/or asolubilizing agent with at least one chemically relatively polar end andat least one chemically relatively non-polar end, and an aromatichydrocarbon; the additive formulation reducing emissions of one or moreof the emissions selected from the group comprising: total hydrocarbons,non-methane hydrocarbons, carbon monoxide, NO_(x), and ozone precursors.The aromatic hydrocarbon may include, but is not limited to, analaphatic derivative of benzene, benzene, xylene, or toluene.

[0094] In a further embodiment, the present invention comprises: anadditive formulation for motor fuels, and a fuel containing theadditive, comprising: from about 10 to about 30 volume percentnitromethane; from about 10 to about 30 volume percent nitroethane; fromabout 40 to about 60 volume percent 1-nitropropane; from about 2 toabout 8 volume percent toluene; and from about 1 to about 3 volumepercent modified ester oil, or a solubilizing agent.

[0095] In yet another embodiment, the present invention comprises: amethod of preparing a fuel additive formulation, comprising: in a mixingvessel adding about 1 part modified ester oil that is substantiallytricresyl phosphate-free or a solubilizing agent; adding about 5 partstoluene; allowing said ester oil or said solubilizing agent and saidtoluene to stand for about 10 minutes at ambient temperature andpressure; adding about 10 parts of nitromethane to said ester oil orsaid solubilizing agent and toluene mixture; adding about 10 parts ofnitroethane to said mixture; adding about 29 parts 1-nitropropane tosaid mixture; and aerating said mixture gently, through a narrow gaugetube at low pressure, and ambient temperature. As embodied herein, theinvention also comprises an additive made by the method of the presentinvention. The invention further comprises a fuel comprising an additivemade by the method of the present invention, as well as the use of theadditive and fuel products as a fuel.

[0096] The fuel may be used in any kind of power unit, including, butnot limited to, a boiler, a turbine, internal combustion engine, or anyother type of appropriate application.

[0097] Both the foregoing general description and the following detaileddescription are exemplary and explanatory only, and are not restrictiveof the invention as claimed. The accompanying drawings, which areincorporated herein by reference, and constitute a part of thespecification, illustrate certain embodiments of the invention and,together with the detailed description, serve to explain the principlesof the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0098] As illustrated by the data in the accompanying tables and graphs,and disclosed in the accompanying claims, the present invention is afuel additive for motor fuels for internal combustion engines,comprising: nitroparaffin, and a solubilizing agent. As embodied herein,the solubilizing agent may be any of various esters, including withoutlimitation: ester oil, alcohol, amines and/or aromatic hydrocarbon. Theinvention comprises an improved fuel additive formulation, and method ofmaking and using the formulation.

[0099] The present inventors have developed a new method of creating astable mixture of nitroparaffins in gasoline and/or diesel fuel, namelyby introduction of an ester oil and/or other solubilizing agent and/oraromatic hydrocarbon component and a mixing procedure of the presentinvention. The present inventors have discovered that low concentrationsof additives reduce emissions, provided the ester oil has been modifiedin accordance with the present invention, or another suitablesolubilizing agent is used. Specifically, the ester oil is modified toremove, or not to introduce, the tricresyl phosphate component ofcommercially available ester oils, and the solubilizing agent has atleast one chemically polar end and at least one chemically non-polarend. Toxicity has been reduced by eliminating, modifying, and/orreplacing components and by reducing the concentration of additive inthe fuel, while reducing emissions.

[0100] Emission reductions are achieved by the removal, introduction,modification, or reduction of various components. For example, tricresylphosphate has been substantially removed from, or not introduced into,commercially available ester oil; a solubilizing agent has beensubstituted for the ester oil; 2-nitropropane has been reduced orremoved from the prior known formulation; the concentration of ester oiland/or solubilizing agent, and nitromethane have been reduced relativeto certain prior known formulations; and/or the overall concentration ofadditive in the fuel has been reduced to a level lower than thattypically used in prior known inventions.

[0101] The present inventors have found that the solubility ofnitromethane, which is normally highly explosive and dangerous, isreduced when introduced as a component of the fuel mixture (c. 170mg/l), to the order of the solubility of gasoline hydrocarbons (c. 120mg/l), and substantially lower than the relatively high water solubilityof a blend of 10% MTBE in gasoline (5000 mg/l). The present inventorshave found that careful balancing of the formulation between the variouscomponents is necessary to make the product safely, while maintainingsuperior emission reduction capacity.

[0102] The present inventors have developed a number of improvementsthat they believe contribute to the beneficial effect of the inventionon emissions.

[0103] First, the ester oil component of the present invention comprisesester oil that has been modified from its commercially available form.In the present invention, ester oil is present not for the purpose ofupper cylinder lubrication in order to reduce friction as it was inprior known formulations but, rather, to enhance the miscibility of thenitroparaffins in gasoline. Commercially available ester oils typicallyinclude various additive packages. The additives typically include avariety of substances that impart various characteristics to the esteroil, such as resistance to combustion, corrosion resistance, stability,and a wide variety of other properties. Prior inventors and theformulations known prior to the present invention taught that the esteroil should be used in the form in which it was commercially available,namely, including the additives found in commercially available esteroil products.

[0104] A number of these additives, however, are highly toxic and areknown environmental contaminants. In addition, some impart propertiesthat are not desired in a fuel formulation, such as flame retardancy.The function of these flame retardants is to preserve the ester oil bypreventing it from burning. In this manner, the ester oil remainsavailable to lubricate the upper cylinder. Some of the prior inventors,including Michaels, specifically taught the benefits that flow fromretaining this property. Moreover, the ester oil is present in such alow concentration in the present invention (i.e., preferably about 1.8volume percent of the additive formulation, or 0.00142 volume percent ofthe fuel) that the flame retardant properties of commercially availableester oil would be expected by persons of ordinary skill in the art tohave a negligible effect, if any, on the performance of the presentinvention.

[0105] The present inventors, however, in contrast to each of the priorknown formulations, have modified the additive package of the ester oil,producing unexpected, beneficial properties. The present inventors,working with commercially available ester oil (Mobil Jet II Oil) haveremoved or eliminated one of the additive components—tricresylphosphate—from the ester oil. Although tricresyl phosphate is toxic, itis present in commercially available formulations of Mobil Jet II Oil.Contrary to the teachings of Michaels to employ commercially availableester oil, the present inventors have modified the ester oil of thepresent invention to be substantially free of this toxic component. Thepresent inventors believe that chemically removing the tricresylphosphate and/or no adding it has modified the ester oil in a mannerbeneficial to the present invention. It is within the knowledge of oneof ordinary skill in the art how to modify an ester oil to remove, ornot to introduce, tricresyl phosphate. In conjunction with the otherfeatures of the present invention, the present inventors have discoveredthat the performance and ability to lower emissions was improved by thepresent invention to an unexpected degree.

[0106] The ester oil in the additive, and the additive in the fuel, arepresent in such low concentrations in the present invention that personsof ordinary skill in the art would have expected that removal of onecomponent of the ester oil would produce no effect on the performance ofthe fuel or its ability to reduce emissions, particularly in view of theteachings of Michaels. Yet, the present inventors have observedprecisely those benefits from the present invention. The presentinventors believe that the removal of the tricresyl phosphate componentof the ester oil may have affected the invention in any of severalpossible ways: by forming a new composition of matter, by modifying theester oil or one or more of its components in some manner; byemulsifying or suspending the nitroparaffins in the fuel; by some formof ionic reaction; by some form of methylation reaction; or by affectingthe solubility of one or more of the components of the presentinvention. The inventors are continuing their investigation.

[0107] Persons of ordinary skill in the art would not have expected thebenefits of the present invention, at the time the invention was made.Removal of the flame retardant involves a trade off. Presence of theflame retardant enables the ester oil to survive combustion and provideincreased upper cylinder lubrication. Prior inventors, such as Michaels,have attributed at least some measure of the improved performance oftheir additives to improved upper cylinder lubrication from the esteroil. On the other hand, the present inventors have discovered thatimproved upper cylinder lubrication is not as critical to the presentinvention as the benefits resulting from the removal of the flameretardant. Whereas Michaels focused on increasing horsepower and fuelefficiency, both of which were related to improving upper cylinderlubrication, the present inventors are attempting to reduce emissions,and in particular emissions on cold start-up. In this regard, removal ofthe tricresyl phosphate from the ester oil produces unexpected,beneficial results. In addition, a solubilizing agent may be substitutedfor the ester oil. The solubilizing agent will be described in greaterdetail in the following pages.

[0108] Second, 2-nitropropane is eliminated from certain embodiments ofthe present invention. Rather, 1-nitropropane is used in lieu of2-nitropropane in these embodiments of the present invention.2-nitropropane is toxic. Removal of 2-nitropropane and replacement withthe less toxic 1-nitropropane enhances safety by reducing potentialexposure to toxics. In contrast, prior known formulations, such asMichaels', used 2-nitropropane exclusively. Others simply failed todistinguish between 1-nitropropane and 2-nitropropane.

[0109] Third, the present inventors have preferably reduced the ratio ofester oil to nitroparaffin. This, in turn, reduces emissions fromcombustion of the ester oil. The ratio of ester oil to nitroparaffin hasbeen reduced to levels well below the levels employed in many priorknown formulations. Michaels teaches the use of ester oil at levels of10 to 90% of the additive formulation, in contrast to the preferredrange of less than about 10% and more preferrably less than about 2%, inthe present invention. Michaels taught that higher concentrations ofester oil were necessary to provide upper cylinder lubrication and tomake a homogenous fuel. He recommends a maximum concentration of 25%ester oil to prevent potential engine fouling. The present inventorshave produced beneficial effects at concentrations far below the lowerlimits of Michaels' range.

[0110] Fourth, toluene has been added in certain embodiments of thepresent invention to enhance engine combustion and improve emissions.Toluene is a component of gasoline. Toluene emulsifies and/or improvesthe solubility of the nitroparaffins in gasoline, reducing the amount ofester oil required. This substitution permits the present inventors tosubstitute a lower emission ingredient (toluene) for a higher emissioningredient (ester oil). In the process, it allows for the properemulsion of the nitroparaffins into the additive and, ultimately, thefuel. The present inventors have found that toluene enhances andaugments the effect of the ester oil in the present invention to enhancethe solubility of nitroparaffins in gasoline.

[0111] Fifth, the present inventors preferably have limited the amountof nitromethane in the formulation. Nitromethane is highly toxic as wellas dangerous. It presents a substantial hazard of explosion and dangerto personal safety. Limiting the concentration of nitromethane reducesthe risk and lowers the toxicity of the additive and, in turn, of thefuel in which it is used.

[0112] The toxic nature of the ingredients was not considered in earlierpatents. The present inventors have made several modifications to theformulation of the present invention to reduce the health risks posed bythe toxic components of the formulation. The inventors have alsomodified the formulation to reduce emission from engines using thepresent invention. The low concentration of additive package in thefuels of the present invention achieves these objectives. The higherconcentration employed in prior known formulations and disclosed inprior patents would result in higher emission of NOx, uncombustednitroparaffins, and total hydrocarbons and non-methane hydrocarbons.They would also tend to increase ozone formation. This would result fromboth the higher concentrations of ester oils and higher concentrationsof nitroparaffins, typically found in the prior known formulations. Atthe relatively high concentrations of ester oils and nitromethanedisclosed in prior known formulations, the fuel would be substantiallymore toxic and pose greater risks to ground water. Emissions would beincreased in general, specifically of toxic materials. The presentinventors have found that only at low concentrations of ester oil andnitromethane can emissions be reduced.

[0113] Sixth, the present inventors preferably have systematized theproduction of the formulation of the present invention. Prior knownadditives have been prepared in small quantities, on a batch basis,often without the benefit of production standards, and little to noattention to production quality control.

[0114] In contrast to the process of the present invention, Michaelsstates that there is no general rule as to the amount of ester oil orsolubilizing agent needed because gasoline varies by type and varieswidely even from the same refinery, depending on multiple variables suchas: the available crudes, refinery operations, and the time of year.Michaels' approach requires continuous monitoring to ensure that properhomogeneous fuels are being blended. Michaels' approach for determiningthe proper blend of ester oil, nitroparaffin, and gasoline requires thatnitroparaffin be added to the gasoline, then that sufficient ester oilbe added to the gasoline in increments. Specifically, Michaels requiresthe addition of a small amount of ester oil followed by mixing, followedby the addition of added amounts of ester oil, repeating the processuntil a homogeneous blend is obtained in the fuel. Michaels does notdisclose the use of a solubilizing agent as disclosed and claimed by thepresent inventors.

[0115] Thus, Michaels' fuels must be mixed in a batch process. Incontrast, the present invention is not so limited. The present inventioncan be added to any fuel. Moreover it can be added in standard amounts,as continuous adjustment is not required in order to make a homogeneousfuel. Thus, the present invention allows the additive to be made andblended in a batch or continuous process that can readily bestandardized for a production-scale operation.

[0116] The present inventors anticipate that a preferred productionscale process would involve the following steps:

[0117] 1. In a clean stainless steel vessel;

[0118] 2. Per 55 gallons of additive, add 1 gallon of modified ester oil(from which substantially all of the tricresyl phosphate has beenremoved), or a solubilizing agent;

[0119] 3. Add 5 gallons of toluene;

[0120] 4. Let ingredients stand 10 minutes at ambient temperature, donot mix;

[0121] 5. Add 10 gallons of nitromethane;

[0122] 6. Add 10 gallons of nitroethane;

[0123] 7. Add 29 gallons of 1-nitropropane;

[0124] 8. Mix by aeration through a narrow tube at low pressure, atambient temperature, venting the mixing vessel to ambient atmosphericpressure;

[0125] 9. Recover nitromethane evaporate through the use of a condenserin the vent;

[0126] 10. Store the additive formulation until ready for use;

[0127] 11. Mix the additive with motor fuel (gasoline, gasoline andMTBE, gasoline and ethanol, and/or gasoline and ethanol and MTBE),preferably at a concentration of 0.1 oz. per gallon of fuel (0.07812%),in gasolines, and preferably at a concentration of 0.2 oz. per gallon offuel (0.15624%) in diesel fuel.

[0128] The inventors believe that the unexpected results of the presentinvention are attributable, at least in part, to the processing andorder of addition of the ingredients, as set forth above. In a preferredembodiment of the present invention, the mixing step preferably isaccomplished by bubbling air at low pressure (10-psig) through a narrowdiameter tube (¼″-⅜″ in diameter), for 10-15 minutes.

[0129] It will be apparent to persons of ordinary skill in the art thatmodifications and variations may be made in the manner of combining theingredients to produce the additive formulation of the presentinvention. For example, the mixing vessel could be epoxy-lined steel orany other suitable material. To the extent that reactive intermediariesor reaction products are formed, the selection of material for themixing vessel may be guided by the desire not to cause any furtherinteraction between the ingredients or, alternatively, to facilitate orcatalyze any reactions that may occur. Moreover, the process may be runon a batch or continuous basis. On a continuous basis, the residencetimes may be adjusted to achieve the above hold times. Moreover, thetoluene and ester oil may be mixed separately, either on a batch orcontinuous basis. Similarly, the nitromethane and nitroethaneingredients may be combined, in order to reduce the material-handlingdifficulties of nitromethane. Thus, it is intended that the inventioninclude the variations and permutations of the method of combining theingredients, provided they come within the scope of the appended claimsand their equivalents.

[0130] The method of preparing the formulation of the present inventionincludes steps to ensure that the components are properly mixed, whilereducing off-gassing which would otherwise occur during processing. Forexample, the present inventors use a simple condenser to collect thenitromethane released during processing.

[0131] Seventh, the present inventors anticipate that, in contrast tothe “homogeneous” “blend” disclosed by Michaels, the present formulationmay preferably comprise one or more reaction products, formed by theinteraction of various of the components of the formulation.Alternatively, modification of the ester oil may have changed thecomposition of the ester oil component. As a further alternative, thepresent inventors may emulsify or suspend the nitroparaffins, ester oil,and/or toluene, in the fuel. Ionic or methylation reactions may haveoccurred, or the combination of the ingredients may affect thesolubility of one or more components in others. The present inventorsare continuing their evaluations, attempting to discover the precisenature of these potential interactions in the present invention.

[0132] Finally, the present invention achieves improved performance, aswell as reduced emissions at lower concentrations of additive than priorknown formulations. Wholly apart from the existence of any reactionproducts, reactive intermediaries, or interaction between the componentsof the invention, the present invention differs from prior knownformulations in various ways. Whereas Michaels combined nitroparaffinsand ester oils in a ratio of from 10 to 90% to 90 to 10%, the presentinvention combines them in proportions outside those ranges, namely,less than about 20%, and preferably less that 10%, ester oil tonitroparaffin. More specifically, the present invention would limit theester oil to nitroparaffin ratio to less than about 10%. In anotherpreferred embodiment of the present invention, the ratio of ester oil tonitroparaffin would be less than about 2%, namely, about 1.8% by volume.

[0133] The amount of additive used per gallon of fuel in the presentinvention is well below the amounts taught by Michaels. Whereas Michaelsincludes additive at levels of 5% to 95% of the amount of gasoline, theadditive of the present invention is typically used in amounts less thanabout 20%. More specifically, the amount of additive is generally lessthan 10%, or 5%. In a preferred embodiment of the present invention, theamount of additive preferably is maintained below about 0.1%, namelyabout 0.08% (or 0.1 of an ounce of additive per gallon of fuel).

[0134] The present invention comprises a fuel additive formulation and amethod of making and using same. The fuel additive formulation of thepresent invention preferably comprises: 1-nitropropane, nitroethane,nitromethane, toluene, and ester oil and/or a solubilizing agent Whenused as a motor fuel for automobiles and other internal combustionengines, the present invention preferably comprises from 0.01% to lessthan about 5% additive by volume, in gasoline.

[0135] In these ranges, the amount of nitroparaffin in Michaels' fuelsis well above the range of the present invention. Whereas Michaelsincludes nitroparaffin in amounts ranging from 0.5% to 85.5%, the amountof nitroparaffin in fuels of the present invention typically ranges from0.064% to 7.6% by volume, and preferably below 0.5% by volume.

[0136] The present invention comprises a continuous range ofcombinations of ester oil and/or toluene, on one hand, andnitroparaffin, on the other. The present inventors believe that thefunction of the ester oil and toluene in the present invention is toallow the nitroparaffins to react with, emulsify with, or become solublein, gasoline. Either toluene and/or ester oil may be used. Preferablyboth are used. The following table illustrates, without limitation, someof the ranges of toluene/ester to nitroparaffin of the presentinvention: TABLE 6 Ratio of Toluene/Ester Oil to Nitroparaffin in theAdditive of the Present Invention Toluene and/or Ester Oil (Volumepercent) Nitroparaffin 0 ≦ x ≦ c. 20% c. 80 ≦ x ≦ c. 100% 0 ≦ x ≦ c. 15%c. 85 ≦ x ≦ c. 100% 0 ≦ x ≦ c. 10% c. 90 ≦ x ≦ c. 100% 0 ≦ x ≦ c. 5% c.95 ≦ x ≦ c. 100% c. 0.1 ≦ x ≦ c. 10% c. 90 ≦ x ≦ c. 99.9% c. 0.1 ≦ x ≦c. 5% c. 95 ≦ x ≦ c. 99.9% c. 0.5 ≦ x ≦ c. 3.5% c. 96.5 ≦ x ≦ c. 99.5%c. 0.5 ≦ x ≦ c. 2.5% c. 97.5 ≦ x ≦ c. 99.5% c. 1.0 ≦ x ≦ c. 2.5% c. 97.5≦ x ≦ c. 99.0%

[0137] The present invention comprises one or more nitroparaffins. Asembodied herein, the nitroparaffins of the present invention comprise:nitromethane, nitroethane, and/or nitropropane. Each may be present incombination with, or to the exclusion of, the others. For example, eachof nitromethane, nitroethane, and nitropropane may comprise from 0% to100% of the nitroparaffin component of the invention identified in Table6. In a preferred embodiment of the present invention, nitromethane isthe preferred nitroparaffin. Preferably, nitromethane is present as 20%to 40% of the nitroparaffin fraction of the additive, and morepreferably, as 20% of the additive formulation. Table 7 illustrates,again without limitation, some of the ranges of nitroparaffins of thepresent invention: TABLE 7 Relative Proportions of VariousNitroparaffins in the Nitroparaffin Component of the Additive of thePresent Invention Nitromethane Nitroethane Nitropropane 0 ≦ x ≦ 100% 0 ≦x ≦ 100% 0 ≦ x ≦ 100% c. 10 ≦ x ≦ c. 50% c. 0 ≦ x ≦ c. 90% c. 0 ≦ x ≦ c.90% to to c. 0 ≦ x ≦ c. 50% c. 0 ≦ x ≦ c. 50% c. 20 ≦ x ≦ c. 40% c. 0 ≦x ≦ c. 80% c. 0 ≦ x ≦ c. 80% to to c. 0 ≦ x ≦ c. 60% c. 0 ≦ x ≦ c. 60%c. 20 c. 0 ≦ x ≦ c. 80% c. 0 ≦ x ≦ c. 80% c. 20 c. 20 c. 60 c. 10 c. 0 ≦x ≦ c. 90% c. 0 ≦ x ≦ c. 90% c. 10 c. 10 c. 80

[0138] Although the present inventors believe that the influence ofnitromethane is more important than other nitroparaffins in the effectof the present invention, nitromethane is relatively more dangerous, interms of material handling, environmental, and public health risk, thannitroethane and/or nitropropane. Nitromethane is more toxic. Moreover,nitromethane poses a greater explosion hazard, necessitating carefulmaterial handling steps that are well known to persons of ordinary skillin the art of handling such volatile compounds. It is imperative inorder to practice the invention that generally accepted materialhandling procedures be followed in order to reduce the risk of bodilyharm and/or explosion hazard.

[0139] Based upon the above continuous ranges of composition, certainranges of the principal components of the present invention areillustrated, without limitation, in Table 8: TABLE 8 Components of thePresent Invention Volume Percent Component of Additive Volume Percent of1-nitropropane 0 ≦ x ≦ 80% 0 ≦ x ≦ 0.0624 Nitroethane 0 ≦ x ≦ 80% 0 ≦ x≦ 0.0624 Nitromethane 0 ≦ x ≦ 80% 0 ≦ x ≦ 0.0624 Toluene 0 ≦ x ≦ 20% 0 ≦x ≦ 0.0156 Ester Oil 0 ≦ x ≦ 20% 0 ≦ x ≦ 0.0156

[0140] The relative amounts of the various nitroparaffins are adjustedto compliment one another, as are the relative amounts of toluene andester oil. The relative amount of nitroparaffin, on one hand, and esteroil and toluene on the other, are also adjusted to compliment oneanother. As will be seen from Table 8, the proportions of the componentsof the present invention are below the ranges of those components inprior known formulations.

[0141] In one preferred embodiment of the present invention, the presentinvention comprises: TABLE 9 Formulation of a Preferred Embodiment ofthe Present Invention Component Parts Proportion of Fuel 1-nitropropane29 0.026 Nitroethane 10 0.009 Nitromethane 10 0.009 Toluene 5 0.00455Ester Oil 1 0.00091

[0142] The ester oil of the present invention includes little to noflame retardant. The present inventors believe that this modificationenables the present invention to reduce emissions on cold start up. Thisresult was surprising, particularly given the long-standing andwidespread use of various commercial, additive-containing ester oils.The present inventors have found, however, that this modificationresults in improved cold start up emissions to a degree that more thancompensates for any negative effect in terms of reduced upper cylinderlubrication through combustion and loss of the ester oil.

[0143] The present inventors have conducted a series of experiments totest the performance of the present invention relative to various knownformulations. These formulations are identified in the followingexamples.

EXAMPLE 1

[0144] Indolene was used as a standard reference fuel. The Indolene waspurchased from Philips Chemical Company: UTG 96 (OBPU9601).

EXAMPLE 2

[0145] Indolene was blended with EChem. The Indolene was the standardreference fuel, of Example 1, above. The EChem formulation used intesting the present invention was obtained from Don Young. The EChemformulation was prepared by: combining 1 gallon of commerciallyavailable Mobil Jet II Oil and 5 gallons of toluene in an epoxy-linedsteel drum that had been flushed; allowing the toluene/ester oil mixtureto stand for 10 minutes; adding 10 gallons of nitromethane; adding 10gallons of nitroethane; adding 29 gallons of 1-nitropropane; andaerating the ingredients through a narrow tube at low pressure, andambient temperature; to produce the additive. The EChem additive wasadded to Indolene at a rate of 0.1 oz. per gallon of fuel.

EXAMPLE 3

[0146] The MAZ 100 formulation of the present invention was prepared asfollows:

[0147] 1. An epoxy-lined 55 gallon drum was flushed;

[0148] 2. 1 gallon of ester oil (modified Mobil Jet II Oil, without thetricresyl phosphate additive) was added;

[0149] 3. 5 gallons of toluene were added;

[0150] 4. The ester oil and toluene were allowed to stand 10 minutes atambient temperature and pressure;

[0151] 5. 10 gallons of nitromethane were added to the mixture;

[0152] 6. 10 gallons of nitroethane were added to the mixture;

[0153] 7. 29 gallons of 1-nitropropane were added to the mixture;

[0154] 8. The components were mixed by gentle aeration, through a narrowtube at low pressure, at ambient temperature, venting the mixing vesselto ambient atmospheric pressure;

[0155] 9. The MAZ 100 additive formulation was then stored until neededfor testing;

[0156]10. The additive was mixed with a reference motor fuel (indolene),at a concentration of 0.1 oz. of MAZ 100 additive per gallon of Indolene(0.07812%).

EXAMPLE 4

[0157] Indolene was procured as noted above in Example 1, from PhillipsChemical Company. MBE was added at 11%.

EXAMPLE 5

[0158] RFG II was secured from Phillips Chemical Company. The RFGformulation used in the testing was California P-II CERT Fuel(0CPCP201).

[0159] The present inventors have run a number of comparisons of thepresent formulation relative to other fuels. The results are tabulatedbelow, in Tables 10 through 13. TABLE 10 MAZ 100 Formulation Results ofEmission Testing (Grams emitted per mile) Indolene EChem 1 MAZ 100Carbon Monoxide 2.090 2.142 2.056 NOx 0.562 0.565 0.546 TotalHydrocarbons 0.311 0.310 0.256 Non-Methane 0.284 0.282 0.229Hydrocarbons Ozone 0.965 1.016 0.775

[0160] TABLE 11 MAZ 100 Formulation vs. EChem 1 Formulation Improvementover Indolene EChem 1 MAZ 100 Difference Carbon Monoxide −2%  2%  4% NOx−1%  3%  4% Total Hydrocarbons  0 18% 18% Non-Methane  1% 19% 18%Hydrocarbons Ozone −5% 20% 25%

[0161] MAZ 100 was tested in a 1992 Plymouth Voyager using a chassisdynamometer. The tests were conducted at the University of California,Riverside, College of Engineering Center for Environmental Research andTechnology (CE-CERT) facility, following the Federal Test Protocol(FTP). A total of four fuels were tested to evaluate the performance ofthe additive in gasoline. The four fuels tested were: (Fuel 1) Indolene;(Fuel 2) Indolene with 0.1 percent by volume MAZ 100; (Fuel 3) Indolenewith 11 percent by volume MTBE; and (Fuel 4) Phase II Federal RFG.

[0162] The MAZ 100 formulation of the present invention was prepared byMagnum Environmental Technologies, Inc., staff prior to the initiationof testing. The staff acquired nitromethane, nitroethane, and1-nitropropane from Angus Chemicals, and Synthetic Ester Oil (TCP-freeMobil Jet 2) from Mobil Chemical Company and they acquired toluene fromVan Waters & Rogers Chemical Distributors. The staff mixed 10 partsnitromethane, 10 parts nitroethane, 29 parts 1-nitropropane, 5 partstoluene, and 1 part ester oil in the manner described above to form theMAZ 100 additive. This material was provided to CE-CERT and used toconduct the tests at CE-CERT.

[0163] CE-CERT acquired certified Indolene (UTG 96) and certified PhaseII California RFG from the Phillips Chemical Company. Commercial GradeMTBE (95% MTBE) was obtained by CE-CERT from ARCO. Magnum EnvironmentalTechnologies supplied the “MAZ 100” additive. CE-CERT staff prepared twoof the four test fuels (Fuel 2 and Fuel 3 above) by blending either the“MAZ 100” additive or MTBE with the appropriate certified gasoline priorto conducting the tests. CE-CERT staff prepared Fuel 2 by placing 0.1percent by volume of the MAZ 100 into Indolene and mixing the resultingtest fuel CE-CERT staff prepared Fuel 3 by placing 11 percent by volumeof MTBE into Indolene and mixing the resulting test fuel. No mixing wasnecessary for Fuel 1 and Fuel 4.

[0164] Each fuel was tested in the 1992 Voyager following the FederalTest Protocol. The test was repeated three times for each fuel. Duringeach test run, exhaust samples were collected in Tedlar bags and thecontents of the each bag were analyzed for the presence of: (1) carbonmonoxide (CO), (2) nitrogen oxides (NO_(x)); (3) non-methanehydrocarbons; and (4) volatile organic compounds (VOCs) that areprecursors to ozone formation to enable prediction of the ozoneformation potential for each test fuel.

[0165] The Federal Test Protocol consists of three phases: Phase 1corresponds to cold starts; Phase 2 corresponds to the transient phasein which the engine speed is varied; and Phase 3 corresponds to the hotstart phase. Exhaust samples were collected during each of the threephases of the FTP in separate bags during each test run. The firstphase, corresponding to cold starts was collected in Bag 1 for each testrun. The exhaust samples corresponding to the transient phase werecollected in Bag 2 for each test run. The exhaust samples correspondingto the hot start phase were collected in Bag 3 for each test run.

[0166] All four test fuels were tested in the same 1992 Plymouth Voyagerand a sufficient volume of test fuel was rinsed through the vehicle'sfuel system and drained to remove traces of the previous test fuel toassure that the results represent the current test fuel. Each test fuelused was also subjected to chemical analysis to verify the hydrocarbonand other compounds present in the test fuel.

[0167] The measured CO, NO_(x), non-methane hydrocarbons, and ozoneformation potential for each test fuel were recorded and compared forall four fuels. The present inventors have run a number of comparisonsof the present formulation relative to other fuels. The results aretabulated below, in Tables 12 and 13. The present invention isrepresented by the information for “MAZ 100”: TABLE 12 MAZ 100Formulation Results of Emissions Testing (grams/mile) Indolene IndolenePlus 11% Plus Indolene MTBE RFG II MAZ 100 Carbon Monoxide 2.090 2.4882.121 2.056 NOx 0.562 0.593 0.527 0.546 Total Hydrocarbons 0.311 0.2370.287 0.256 Non-Methane 0.284 0.213 0.255 0.229 Hydrocarbons Ozone 0.966N/A* 0.807 0.775

[0168]

[0169] Based upon the above information, the following percentageimprovements in emissions were observed: TABLE 13 MAZ 100 FormulationEmissions Improvement Relative to Indolene Indolene Plus 11% IndolenePlus MTBE RFG II MAZ 100 Carbon Monoxide −19%  −1%  2% NOx −5%  6%  3%Total Hydrocarbons 24%  8% 18% Non-Methane 25% 10% 19% HydrocarbonsOzone N/A* 16% 20%

[0170] For the test vehicle used, the present invention produced resultssuperior to the reference fuel, and MTBE, on numerous criteria. Thepresent inventors believe that the results of the present invention maynot be reproduced using a vehicle made after approximately 1994, as suchvehicles are equipped with oxygen sensors and advanced computer enginecontrols that can rapidly adjust fuel to oxygen ratios and timingminimizing the beneficial effects of the additive on emissions.Nonetheless, the present inventors believe that the beneficial effectsof the present invention in the 1992 vehicle are due to themodifications and variations of the invention relative to prior knownformulations that failed to achieve the beneficial effects of thepresent invention.

[0171] It will be apparent to those skilled in the art that variousmodifications and variations can be made in the construction andconfiguration of the present invention without departing from the scopeor spirit of the invention. Thus, it is intended that the presentinvention cover the modifications and variations of the inventionprovided they come within the scope of the appended claims and theirequivalents. For example, the additive formulation may be preparedcomprising a nitroparaffin and a solubilizing agent.

[0172] As illustrated by the data in the accompanying tables and graphs,and disclosed in the accompanying claims, a preferred embodiment of thepresent invention is a fuel additive for motor fuels for internalcombustion engines, comprising nitroparaffin and a solubilizing agent,wherein the solubilizing agent comprises at least one chemically polarend and at least one chemically non-polar end. The chemically polar endsmay comprise ether groups, or any other suitable chemically polar group.The chemically non-polar ends may comprise hydrocarbon groups, or anyother suitable chemically non-polar group.

[0173] A preferred embodiment of the present invention is a fueladditive for motor fuels for internal combustion engines, comprisingnitroparaffin and an ester compound, wherein the ester compoundcomprises at least one chemically polar end and at least one chemicallynon-polar end. The chemically polar ends may comprise ether groups, orany other suitable chemically polar group. The chemically non-polar endsmay comprise hydrocarbon groups, or any other suitable chemicallynon-polar group.

[0174] A preferred embodiment of the present invention is a fueladditive for motor fuels for internal combustion engines, comprisingnitroparaffin and a simple ester compound, wherein the simple estercompound comprises at least one chemically polar end and at least onechemically non-polar end. The chemically polar ends may comprise ethergroups, or any other suitable chemically polar group. The chemicallynon-polar ends may comprise hydrocarbon groups, or any other suitablechemically non-polar group. The simple ester compound may be prepared byreacting ether alcohols and monobasic acids, or any other suitablereactants that would give rise to a simple ester compound. The simpleester compound may be a simple ether alcohol ester.

[0175] A preferred embodiment of the present invention is a fueladditive for motor fuels for internal combustion engines, comprisingnitroparaffin and an amino alkane compound, wherein the amino alkanecompound comprises at least one chemically polar end and at least onechemically non-polar end. The chemically polar ends may comprise aminogroups, or any other suitable chemically polar group. The chemicallynon-polar ends may comprise hydrocarbon groups, or any other suitablechemically non-polar group. The amino alkane compound may have thefollowing formula:

[0176] wherein R₁ and R₂ are either hydrogen, alkyl (methyl, ethyl,propyl, or any other compatable group) or aryl, and n can vary from 1 to8. The main hydrocarbon chain may also be branched. The compound mayalso contain two or more amino groups having alkyl or aryl substituents.Compounds containing various combinations of ether, ester and aminogroups are also expected to be useful as solubilizing agents fornitroalkanes in gasoline.

[0177] In a preferred embodiment of the present invention, the aminoalkane compounds may further comprise:

[0178] Where n=6 would be (1-methylaminoheptane);

[0179] 1-Dimethylamino-3-hexanoyloxypropane;

[0180] 1-(N-Ethyl-N-methyl)amino-2 proyloxyethane; and

[0181] 1-(N-Ethyl-N-methyl)amino-2-oxy-pentanoyloxyethyl ether.

[0182] The simple ether alcohol esters may be synthesized by severalroutes known by persons of ordinary skill in the art. The acid chlorideroute was chosen to synthesize the bulk of these esters since thesynthesis is relatively fast, and is easy to accomplish in excellentyields. This route would not be the choice for commercial productionsince the starting acid chlorides are considerably more expensive thanthe corresponding acids. Also, the acid chloride synthesis involves theuse of ether, a volatile and explosive compound.

[0183] The preferred commercial route to obtain the identical esterswould be by the direct reaction of the alcohol with the acid, over anacid resin catalyst. This route involves the removal of water duringreaction, several filtrations, and a distillation step, common methodsin industrial chemistry.

[0184] The following section describes six additional examples forpreparing these esters using two alcohols and two acid chlorides, in thepresence of an amine. Example 12 describes the synthesis of one of theseesters using the direct reaction route of adding the acid to thealcohol, in the presence of an acid resin catalyst. In Example 12, theacid catalyst is recovered and is reusable, and so is the n-octane,which is recovered by distillation. Thus Example 12 would be the moreeconomical and safe route to obtain these esters.

EXAMPLE 6 Preparation of Diethylene Glycol Ethyl Ether (carbitol™) Esterof n-Octanoic Acid (C8)

[0185] A 3 liter flask equipped with a magnetic stirrer, thermometer andaddition funnel, was charged with 147 grams of diethylene glycol ethylether, 111 grams of triethyl amine and 200 ml of diethyl ether. Theflask was than partially immersed in a cold water bath. The additionfunnel was then charged with 163 grams of n-octanoyl chloride. The acidchloride was added to the flask while stirring. The entire mixture wasmaintained in the water bath, while stirring, for two hours, to allowthe exothermic reaction to subside. After the exotherm subsided, theflask was kept in cold water for an additional hour. The reactionmixture was then filtered to remove the amine hydrochloride solid. Thefiltrate was then vacuum stripped from a heated water bath atapproximately 200 mm pressure. The residue was then extracted once witha 2% aqueous sodium sulfate and was dried over solid anhydrous sodiumsulfate and filtered to give the final product.

EXAMPLE 7 Preparation of Diethylene Glycol Ethyl Ether Ester ofn-Hexanoic Acid (C6)

[0186] A 3 liter flask equipped with a magnetic stirrer, thermometer andaddition funnel, was charged with 147 grams of diethylene glycol ethylether, 111 grams of triethyl amine and 200 ml of diethyl ether. Theflask was then partially immersed in a cold water bath. The additionfunnel was then charged with 163 grams of n-hexanoyl chloride. The acidchloride was added to the flask while stirring. The entire mixture wasmaintained in the water bath, while stirring, for two hours, to allowthe exothermic reaction to subside. After the exotherm subsided, theflask was kept in cold water for an additional hour.

[0187] The reaction mixture was then filtered to remove the amionehydrochloride solid. The filtrate was then vacuum stripped from a heatedwater bath at approximately 200 mm pressure. The residue was thenextracted once with a 2% aqueous sodium sulfate and was dried over solidanhydrous sodium sulfate and filtered to give the final product.

EXAMPLE 8 Preparation of Ethylene Glycol Ethyl Ether (cellosolve™) Esterof n-Hexanoic Acid

[0188] A 3 liter flask equipped with a magnetic stirrer, thermometer andaddition funnel, was charged with 147 grams of diethylene glycol ethylether, 111 grams of triethyl amine and 200 ml of diethyl ether. Theflask was then partially immersed in a cold water bath. The additionfunnel was then charged with 163 grams of n-hexanoyl chloride. The acidchloride was added to the flask while stirring. The entire mixture wasmaintained in the water bath, while stirring, for two hours, to allowthe exothermic reaction to subside. After the exotherm subsided, theflask was kept in cold water for an additional hour.

[0189] The reaction mixture was then filtered to remove the amionehydrochloride solid. The filtrate was then vacuum stripped from a heatedwater bath at approximately 200 mm pressure. The residue was thenextracted once with a 2% aqueous sodium sulfate and was dried over solidanhydrous sodium sulfate and filtered to give the final product.

EXAMPLE 9 Preparation of Ethoxy Ethyl Ether Ester of n-Octanoic Acid

[0190] A 3 liter flask equipped with a magnetic stirrer, thermometer andaddition funnel, was charged with 147 grams of diethylene glycol ethylether, 111 grams of triethyl amine and 200 ml of diethyl ether. Theflask was then partially immersed in a cold water bath. The additionfunnel was then charged with 163 grams of n-hexanoyl chloride. The acidchloride was added to the flask while stirring. The entire mixture wasmaintained in the water bath, while stirring, for two hours, to allowthe exothermic reaction to subside. After the exotherm subsided, theflask was kept in cold water for an additional hour.

[0191] The reaction mixture was then filtered to remove the amionehydrochloride solid. The filtrate was then vacuum stripped from a heatedwater bath at approximately 200 mm pressure. The residue was thenextracted once with a 2% aqueous sodium sulfate and was dried over solidanhydrous sodium sulfate and filtered to give the final product.

EXAMPLE 10 Preparation of Ethoxy Ether Ester with a mixture ofn-Octanoic Acid and n-Hexanoic Acids

[0192] A 3 liter flask equipped with a magnetic stirrer, thermometer andaddition funnel, was charged with 147 grams of diethylene glycol ethylether, 111 grams of triethyl amine and 200 ml of diethyl ether. Theflask was then partially immersed in a cold water bath. The additionfunnel was then charged with 81.5 grams of n-octanoyl chloride and 81.5grams of n-hexanoyl chloride. The acid chloride was added to the flaskwhile stirring, for two hours, to allow the exothermic reaction tosubside. After the exotherm subsided, the flask was kept in cold waterfor an additional hour.

[0193] The reaction mixture was then filtered to remove the amionehydrochloride solid. The filtrate was then vacuum stripped from a heatedwater bath at approximately 200 mm pressure. The residue was thenextracted once with a 2% aqueous sodium sulfate and was dried over solidanhydrous sodium sulfate and filtered to give the final product.

EXAMPLE 11 Preparation of Diethylene Glycol Ethyl Ether Ester with amixture of n-Octanoic Acid and n-Haxanoic Acids

[0194] A 3 liter flask equipped with a magnetic stirrer, thermometer andaddition funnel, was charged with 147 grams of diethylene glycol ethylether, 111 grams of triethyl amine and 200 ml of diethyl ether. Theflask was then partially immersed in a cold water bath. The additionfunnel was then charged with 81.5 grams of n-octanoyl chloride and 81.5grams of n-hexanoyl chloride. The acid chloride was added to the flaskwhile stirring. The entire mixture was maintained in the water bath,while stirring, for two hours, to allow the exothermic reaction tosubside. After the exotherm subsided, the flask was kept in cold waterfor an additional hour.

[0195] The reaction mixture was then filtered to remove the amionehydrochloride solid. The filtrate was then vacuum stripped from a heatedwater bath at approximately 200 mm pressure. The residue was thenextracted once with a 2% aqueous sodium sulfate and was dried over solidanhydrous sodium sulfate and filtered to give the final product.

EXAMPLE 12 Preparation of Diethylene Glycol Ethyl Ether Ester ofn-Octanoic Acid by Direct Esterefication

[0196] A 5 liter reaction flask equipped with a mechanical stirrer,thermometer, addition funnel and a Dean-Stark distillation adapter wascharged with 1600 ml of diethylene glycol monoethyl ether, 1260 ml ofoctanoic acid, 600 ml of n-octane and 79.6 grams of commercial Amberlistcatalyst resin (polystyrene sulfonic acid).

[0197] The reaction mixture was refluxed to remove 1366 ml of water fromthe reaction, over 1.5 hours. The flask was then cooled to roomtemperature in a water bath, and the reaction product was then filteredto remove the catalyst resin. The reaction product was then washed twicewith cold water once with 0.5 molar sodium hydroxide, then twice againwith cold water. The material was then vacuum stripped at 125 mmpressure and 125 C.

[0198] The purity of the final product was determined by measuring theasponification number (by titration). Saponification number for theproduct was 221 mg KOH/grams, versus a theoretical of 216 mg KOH/grams.

[0199] The miscibility and solubilizing effects were determinedexperimentally by simple mixing experiments. These experiments involvedboth commercially purchased gasoline and Indolene, a synthetic“standard” used in the industry to simulate gasolines, and by mixingthem with nitroparaffins, using the above mentioned solubilizing agents.The solubility experiments were set up in the following fashion.

[0200] Each experiment used the same size of test tube (13*100 mm). Toeach test tube, 5 cc of either gasoline or indolene were added. Thegasoline was purchased from Texaco, lowest grade, no lead. Indolene wasused as received from Magnum Environmental Technologies. The Mobil JetII Oil was also used as received from Magnum Environmental Technologies.

[0201] To the gasoline or Indolene containing test tubes, 1 cc ofnitromethane and either 0.2 cc toluene (Tables 14 and 15), or no toluene(Tables 16 and 17) were added. Both the nitromethane and toluene were asreceived from Aldrich Chemical. After these additions were made, eachtest tube was inverted three times to insure proper mixing.

[0202] After mixing, each test tube exhibited two phases of liquid,indicating non-solubility.

[0203] A specific solubilizing agent was added, by drops, to each testtube. After each drop of solubilizing agent, the test tube was invertedthree times, and allowed to stand and come to equilibrium for fifteenminutes. The solubilizing agent additions were continued until the phaseseparation disappeared, thus a complete solution occurred. Looking atthe results of Table 14, therefore, it means that it required 21 dropsof PPL solubilizing agent 272-60 to solubilize the mixture, 26 drops ofPPL solubilizing agent 305-35 and 39 drops of the Mobil Jet II Oil.TABLE 14 SOLUBILITY EXPERIMENTS GASOLINE Gasoline Toluene NitromethaneExample # PPL# Acid Alcohol cc cc cc # Drops* 1 272-60 C8 carbitol 5 0.21 21 2 305-18 C6 carbitol 5 0.2 1 22 3 305-17 C6 cellosolve 5 0.2 1 21 4305-19 C8 cellosolve 5 0.2 1 23 5 305-24 Mix C6-C8 cellosolve 5 0.2 1 206 305-20 Mix C6-C8 carbitol 5 0.2 1 20 7 305-35 C8 carbitol 5 0.2 1 26Mobil Jet Oil — — 5 0.2 1 39

[0204] TABLE 15 SOLUBILITY EXPERIMENTS INDOLENE Gasoline TolueneNitromethane Example # PPL# Acid Alcohol cc cc cc # Drops* 1 272-60 C8carbitol 5 0.2 1 22 2 305-18 C6 carbitol 5 0.2 1 21 3 305-17 C6cellosolve 5 0.2 1 20 4 305-19 C8 cellosolve 5 0.2 1 22 5 305-24 MixC6-C8 cellosolve 5 0.2 1 25 6 305-20 Mix C6-C8 carbitol 5 0.2 1 19 7305-35 C8 carbitol 5 0.2 1 25 Mobil Jet Oil — — 5 0.2 1 36

[0205] TABLE 16 SOLUBILITY EXPERIMENTS GASOLINE Gasoline TolueneNitromethane Example # PPL# Acid Alcohol cc cc cc # Drops* 1 272-60 C8carbitol 5 0 1 14 2 305-18 C6 carbitol 5 0 1 14 3 305-17 C6 cellosolve 50 1 15 4 305-19 C8 cellosolve 5 0 1 14 5 305-24 Mix C6-C8 cellosolve 5 01 14 6 305-20 Mix C6-C8 carbitol 5 0 1 14 7 305-35 C8 carbitol 5 0 1 14Mobil Jet Oil — — 5 0 1 18

[0206] TABLE 17 SOLUBILITY EXPERIMENTS INDOLENE Gasoline TolueneNitromethane Example # PPL# Acid Alcohol cc cc cc # Drops* 1 272-60 C8carbitol 5 0 1 11 1 272-60 C8 carbitol 5 0 1 11 2 305-18 C6 carbitol 5 01 10 3 305-17 C6 cellosolve 5 0 1 11 4 305-19 C8 cellosolve 5 0 1 11 5305-24 Mix C6-C8 cellosolve 5 0 1 10 6 305-20 Mix C6-C8 carbitol 5 0 111 7 305-35 C8 carbitol 5 0 1 11 Mobil Jet Oil — — 5 0 1 16

[0207] The present inventors have developed a new method of creating astable mixture of nitroparaffins in gasoline and/or diesel fuel, namelyby introduction of a solubilizing agent, wherein the solubilizing agentcomprises at least one chemically polar end and at least one chemicallynon-polar end, and a mixing procedure of the present invention. Thepresent inventors have discovered that low concentrations of fueladditives reduce emissions. Toxicity has been reduced by eliminating,modifying and/or replacing components and by reducing the concentrationof additive in the fuel, while reducing emissions.

[0208] It will be apparent to those skilled in the art that variousmodifications and variations can be made in the construction andconfiguration of the present invention without departing from the scopeor spirit of the invention. Thus, it is intended that the presentinvention cover the modifications and variations of the inventionprovided they come within the scope of the appended claims and theirequivalents.

We claim:
 1. An additive formulation for a fuel comprising:nitroparaffin; and solubilizing agent; said fuel resulting in reducedemissions relative to a fuel not containing said additive.
 2. Theformulation of claim 1, wherein said solubilizing agent comprisesrelatively polar and non-polar ends.
 3. The formulation of claim 1,wherein said solubilizing agent is selected from the group consistingof: ester oil, ester alcohol, simple ester alcohol, ester ether alcohol,ester amine, and aromatic hydrocarbon.
 4. The formulation of claim 1,wherein said nitroparaffin comprises: one or more nitroparaffincomponents selected from the group consisting of: 1-nitropropane,2-nitropropane, nitroethane, and nitromethane.
 5. The formulation ofclaim 1, further comprising an aromatic hydrocarbon.
 6. The formulationof claim 1, further comprising an aliphatic derivative of benzene. 7.The formulation of claim 5, wherein said aromatic hydrocarbon isselected from the group consisting of: benzene, ethyl benzene, xylene,and toluene.
 8. An additive formulation for a fuel comprising: a firstcomponent, comprising 0 to 99 volume percent of one or morenitroparaffin components, selected from the group consisting of:1-nitropropane, 2-nitropropane, nitroethane, and nitromethane; a secondcomponent, comprising substantially the balance of the additiveformulation, one or more selected from the group consisting of: esteroil, ester alcohol, simple ester alcohol, ester amine, and aromatichydrocarbon; the additive formulation for reducing one or more emissionsselected from the group consisting of: total hydrocarbons, non-methanehydrocarbons, carbon monoxide, NO_(x), and ozone precursors.
 9. Theformulation of claim 8, wherein said first component comprises: 20 to 40volume percent nitromethane, and 60 to 80 volume percent of one or morenitroparaffin components, selected from the group consisting of:1-nitropropane, 2-nitropropane, and nitroethane.
 10. The formulation ofclaim 8, further comprising less than 20 volume percent of an aromatichydrocarbon and less than 10 volume percent ester oil.
 11. Theformulation or fuel of claim 8, wherein said formulation is adapted foruse in a power unit selected from the group consisting of: boiler,turbine, and internal combustion engine.
 12. The formulation or fuel ofclaim 11, wherein said internal combustion engine is selected from thegroup consisting of: a gasoline engine and a diesel engine.
 13. Theformulation of claim 1, wherein said reduced emissions comprise areduction in one or more emissions selected from the group consistingof: carbon monoxide, NO_(x), total hydrocarbon, non-methane hydrocarbon,and ozone precursors.
 14. The formulation of claim 1 or 8, wherein saidsolubilizing agent comprises less than about 2 volume percent of saidadditive formulation for reducing one or more emissions selected fromthe group consisting of: exhaust emissions and hydrocarbon emissions.15. The formulation of claim 1 or 8, wherein the nitroparaffin componentcomprises less than about 10 volume percent of said formulation.
 16. Afuel for reducing emissions from a motor vehicle, comprising: anadditive formulation comprising: nitroparaffin; and solubilizing agent;said fuel resulting in reduced emissions relative to a motor fuel notcontaining said additive.
 17. The fuel of claim 16, wherein saidsolubilizing agent further comprises relatively polar and non-polarends.
 18. The fuel of claim 16, wherein said solubilizing agent isselected from the group consisting of: ester oil, ester alcohol, simpleester alcohol, ester ether alcohol, ester amine, and aromatichydrocarbon.
 19. The fuel of claim 16, wherein said nitroparaffinfurther comprises one or more nitroparaffin components selected from thegroup consisting of: 1-nitropropane, 2-nitropropane, nitroethane, andnitromethane.
 20. The fuel of claim 16, further comprising an aromatichydrocarbon.
 21. The fuel of claim 16, further comprising an aliphaticderivative of benzene.
 22. The fuel of claim 20, wherein said aromatichydrocarbon is selected from the group consisting of: benzene, ethylbenzene, xylene, and toluene.
 23. A fuel for reducing emissions from amotor vehicle, comprising: an additive formulation comprising: a firstcomponent, comprising 0 to 99 volume percent of one or morenitroparaffin components, selected from the group consisting of:1-nitropropane, 2-nitropropane, nitroethane, and nitromethane; a secondcomponent, comprising the balance of the additive formulation, one ormore selected from the group consisting of: ester oil, ester alcohol,simple ester, ester ether alcohol, ester amine, and aromatichydrocarbon; the additive formulation for reducing one or more of theemissions selected from the group consisting of: total hydrocarbons,non-methane hydrocarbons, carbon monoxide, NO_(x), and ozone precursors.24. The fuel of claim 23, wherein said first component furthercomprises: 20 to 40 volume percent nitromethane, and 60 to 80 volumepercent of one or more nitroparaffin components, selected from the groupconsisting of: 1-nitropropane, 2-nitropropane, and nitroethane.
 25. Thefuel of claim 23, further comprising an additive comprising ester oiland toluene.
 26. The fuel of claim 23, further comprising an additivecomprising less than 20 volume percent toluene and less than 10 volumepercent ester oil.
 27. The fuel of claim 16 or 23, wherein saidformulation is adapted for use in a power unit selected from the groupconsisting of: boiler, turbine, and internal combustion engine.
 28. Thefuel of claim 27, wherein said internal combustion engine is selectedfrom the group consisting of: a gasoline engine and a diesel engine. 29.The fuel of claim 16, wherein said reduced emissions comprise areduction in one or more emissions selected from the group consistingof: carbon monoxide, NO_(x), total hydrocarbon, non-methane hydrocarbon,and ozone precursors.
 30. The fuel of claim 16 or 23, wherein saidsolubilizing agent comprises less than about 2 volume percent of saidadditive formulation to reduce one or more emissions selected from thegroup consisting of: exhaust emissions and hydrocarbon emissions. 31.The fuel of claim 16 or 23, wherein said nitroparaffin comprises lessthan about 10 volume percent of said formulation.
 32. An additiveformulation for motor fuels comprising: nitroparaffin; and asolubilizing agent; wherein said solubilizing agent contains at leastone chemically relatively polar end and at least one chemicallyrelatively non-polar end; said fuel resulting in reduced emissionsrelative to motor fuel not containing said additive.
 33. The formulationof claim 32, wherein said nitroparaffin comprises: one or morenitroparaffin components, selected from the group consisting of:1-nitropropane, 2-nitropropane, nitroethane, and nitromethane.
 34. Anadditive formulation for motor fuels comprising: a first component,comprising 0 to 99 volume percent of one or more nitroparaffincomponents, selected from the group consisting of: 1-nitropropane,2-nitropropane, nitroethane, and nitromethane; a second component,comprising substantially the balance of the additive formulation, one ormore selected from the group consisting of: solubilizing agentcomprising at least one chemically relatively polar end and at least onechemically relatively non-polar end; the additive formulation reducingemissions of one or more of the emissions selected from the groupconsisting of: total hydrocarbons, non-methane hydrocarbons, carbonmonoxide, NO_(x), and ozone precursors.
 35. The formulation of claim 34,wherein said first component comprises: 20 to 40 volume percentnitromethane, and 60 to 80 volume percent of one or more nitroparaffincomponents, selected from the group consisting of: 1-nitropropane,2-nitropropane, and nitroethane.
 36. The formulation of claim 34,further comprising less than 20 volume percent of an aromatichydrocarbon and less than 10 volume percent said solubilizing agent. 37.An additive formulation for motor fuels comprising: from about 10 toabout 30 volume percent nitromethane; from about 10 to about 30 volumepercent nitroethane; from about 40 to about 60 volume percent1-nitropropane; from about 2 to about 8 volume percent toluene; and fromabout 0.5 to about 3 volume percent solubilizing agent, wherein saidsolubilizing agent comprises at least one chemically relatively polarend and at least one chemically relatively non-polar end.
 38. Theformulation of claim 37, further comprising: about 20 volume percentnitromethane, about 20 volume percent nitroethane, and about 60 volumepercent 1-nitropropane.
 39. The formulation of claim 37, furthercomprising about 10 volume percent toluene and about 2 volume percent ofsaid solubilizing agent.
 40. The additive formulation of claim 32, 34,or 37, further comprising an aromatic hydrocarbon.
 41. The formulationof claim 32, 34, or 37, further comprising an aliphatic derivative ofbenzene.
 42. The formulation of claim 40, wherein said aromatichydrocarbon is selected from the group consisting of: benzene, ethylbenzene, xylene, and toluene.
 43. The formulation of claim 32, 34, or37, wherein said formulation is adapted for use in a power unit selectedfrom the group consisting of: boiler, turbine, and internal combustionengine.
 44. The formulation of claim 32, 34, or 37, wherein said atleast one chemically relatively polar end is selected from the groupconsisting of: an ether group and an amine group.
 45. The formulation ofclaim 32, 34, or 37, wherein said at least one chemically relativelynon-polar end is selected from the group consisting of: a hydrocarbongroup, an aromatic hydrocarbon group, and an aliphatic hydrocarbongroup.
 46. The formulation of claim 32, 34, or 37, wherein saidsolubilizing agent is selected from the group consisting of: an ester,an ester alcohol, a simple ester alcohol, a simple ether alcohol ester,an ether and ester amine compound.
 47. The formulation of claim 46,wherein said ester is prepared by the reaction of an ether alcohol witha monobasic acid.
 48. The formulation of claim 46, wherein said ester isprepared by the reaction of an ether alcohol, an acid chloride, and anamine.
 49. The formulation of claim 32, 34, or 37, wherein saidsolubilizing agent is an amino alkane compound.
 50. The formulation ofclaim 32, 34, or 37, wherein said solubilizing agent is an amino alkanecompound of the formula:

wherein R₁ is selected from the group consisting of: hydrogen, an alkylgroup, and an aryl group; wherein R₂ is selected from the groupconsisting of: hydrogen, an alkyl group, and an aryl group; and whereinn equals from one to eight.
 51. The formulation of claim 32 or 37,wherein said reduced emissions comprise a reduction in one or moreemissions selected from the group consisting of: carbon monoxide,NO_(x), total hydrocarbon, non-methane hydrocarbon, and ozoneprecursors.
 52. The formulation of claim 32, 34, or 37, wherein saidsolubilizing agent comprises less than about 2 volume percent of saidadditive formulation to reduce one or more emissions selected from thegroup consisting of: exhaust emissions and hydrocarbon emissions. 53.The formulation of claim 32, 34, or 37, wherein said nitroparaffincomprises less than about 10 volume percent of said formulation.
 54. Amethod of preparing a fuel additive formulation, comprising: in a mixingvessel; adding about 1 part solubilizing agent, wherein saidsolubilizing agent comprises at least one chemically relatively polarend and at least one chemically relatively non-polar end; allowing saidsolubilizing agent to stand for 10 minutes at ambient temperature andpressure; adding about 10 parts nitromethane to said solubilizing agentmixture; adding about 10 parts nitroethane to said mixture; adding about29 parts 1-nitropropane to said mixture; aerating said mixture gently,through a narrow gauge tube at low pressure, and ambient temperature;storing the additive.
 55. The method of claim 54, further comprisingadding about 5 parts toluene, prior to the step of allowing saidsolubilizing agent to stand.
 56. The additive made by the method ofclaim
 54. 57. A motor fuel, comprising an additive made by the method ofclaim
 54. 58. A motor fuel, comprising an additive made by the method ofclaim 54, at a concentration of about 0.1 oz. of additive per gallon ofmotor fuel.
 59. A fuel for vehicles, comprising an additive made by themethod of claim
 54. 60. A fuel for reducing emissions from a vehicle,comprising: formulating an additive comprising: nitroparaffin; andsolubilizing agent, wherein said solubilizing agent comprises at leastone chemically relatively polar end and at least on chemicallyrelatively non-polar end; adding said additive to said fuel at aconcentration of about 1-99 volume percent of said additive to saidfuel.
 61. The fuel of claim 60, wherein said nitroparaffin furthercomprises one or more nitroparaffin components, selected from the groupconsisting of: 1-nitropropane, 2-nitropropane, nitroethane, andnitromethane.
 62. A fuel for reducing emissions from a motor vehicle,comprising: formulating an additive comprising: a first component,comprising 0 to 99 volume percent of one or more nitroparaffincomponents, selected from the group consisting of: 1-nitropropane,2-nitropropane, nitroethane, and nitromethane; a second component,comprising substantially the balance of the additive formulation, one ormore selected from the group consisting of: solubilizing agentcomprising at least one chemically relatively polar end and at least onechemically relatively non-polar end; the additive formulation reducingone or more emissions selected from the group consisting of: totalhydrocarbons, non-methane hydrocarbons, carbon monoxide, NO_(x), andozone precursors.
 63. The fuel of claim 62, wherein said first componentfurther comprises: 20 to 40 volume percent nitromethane, and 60 to 80volume percent of one or more nitroparaffin components, selected fromthe group consisting of: 1-nitropropane, 2-nitropropane, andnitroethane.
 64. The fuel of claim 62, further comprising an additivecomprising less than 20 volume percent toluene and less than 10 volumepercent said solubilizing agent.
 65. A fuel for reducing emissions froman automobile, comprising: formulating an additive comprising: fromabout 10 to about 30 volume percent nitromethane; from about 10 to about30 volume percent nitroethane; from about 40 to about 60 volume percent1-nitropropane; from about 2 to about 8 volume percent toluene; fromabout 1 to about 3 volume percent solubilizing agent, wherein saidsolubilizing agent comprises at least one chemically relatively polarend and at least one chemically relatively non-polar end; and addingsaid additive to the fuel.
 66. The fuel of claim 65, further comprising:about 20 volume percent nitromethane, about 20 volume percentnitroethane, and about 60 volume percent 1-nitropropane.
 67. The fuel ofclaim 65, further comprising about 10 volume percent toluene and about 2volume percent of said solubilizing agent.
 68. The fuel of claim 60, 62,or 65, further comprising an aromatic hydrocarbon.
 69. The fuel of claim60, 62, or 65, further comprising an aliphatic derivative of benzene.70. The fuel of claim 68, wherein said aromatic hydrocarbon is selectedfrom the group consisting of: benzene, ethyl benzene, xylene, andtoluene.
 71. The fuel of claim 60, 62, or 65, wherein said formulationis adapted for use in a power unit selected from the group consistingof: boiler, turbine, and internal combustion engine.
 72. The fuel ofclaim 60, 62, or 65, wherein said at least one chemically relativelypolar end is selected from the group consisting of: an ether group andan amine group.
 73. The fuel of claim 60, 62, or 65, wherein said atleast one chemically relatively non-polar end is selected from the groupconsisting of: a hydrocarbon group, an aromatic hydrocarbon group, andan aliphatic hydrocarbon group.
 74. The fuel of claim 60, 62, or 65,wherein said solubilizing agent is selected from the group consistingof: an ester alcohol, a simple ester alcohol, a simple ester etheralcohol, and an ester amine compound.
 75. The fuel of claim 74, whereinsaid ester is prepared by the reaction of an ether alcohol with amonobasic acid.
 76. The fuel of claim 74, wherein said ester is preparedby the reaction of an ether alcohol, an acid chloride, and an amine. 77.The fuel of claim 60, 62, or 65, wherein said solubilizing agent is anamino alkane compound.
 78. The fuel of claim 60, 62, or 65, wherein saidsolubilizing agent is an amino alkane compound of the formula:

wherein R₁ is selected from the group consisting of: hydrogen, an alkylgroup, and an aryl group; wherein R₂ is selected from the groupconsisting of: hydrogen, an alkyl group, and an aryl group; and whereinn equals from one to eight.
 79. The fuel of claim 71, wherein saidinternal combustion engine is selected from the group consisting of agasoline engine and a diesel engine.
 80. The fuel of claim 60, 62, or65, wherein said reduced emissions comprise a reduction in one or moreemissions selected from the group consisting of: carbon monoxide,NO_(x), total hydrocarbon, non-methane hydrocarbon, and ozoneprecursors.
 81. The formulation of claim 60, 62, or 65, wherein saidester oil comprises less than about 2 volume percent of said additiveformulation to reduce one or more emissions selected from the groupconsisting of: exhaust emissions and hydrocarbon emissions.
 82. Theformulation of claim 60, 62, or 65, wherein said nitroparaffin comprisesless than about 10 volume percent of said formulation.
 83. An additiveformulation for motor fuels comprising: nitroparaffin substantially freeof 2-nitropropane; and ester oil; said additive added to said fuel to afinal concentration of less than about 5 volume percent of said additivein said fuel; said fuel resulting in reduced emissions relative to motorfuel not containing said additive when burned in an internal combustionengine.
 84. The formulation of claim 83, wherein said nitroparaffinfurther comprises: one or more nitroparaffin components selected fromthe group consisting of: 1-nitropropane, nitroethane, and nitromethane.85. The formulation of claim 83, wherein said nitroparaffin furthercomprises about 10 to 40 volume percent nitromethane.
 86. Theformulation of claim 83, wherein said ester oil is substantially free oftricresyl phosphate.
 87. The formulation of claim 83, further comprisingan aromatic hydrocarbon.
 88. The formulation of claim 87, wherein saidaromatic hydrocarbon is toluene.
 89. The formulation of claim 83,wherein said formulation is added to said fuel at a concentration ofless than about 0.5 oz. of said formulation per gallon of fuel.
 90. Anadditive formulation for motor fuels comprising: a first component,comprising 0 to 80 volume percent of one or more nitroparaffincomponents, selected from the group consisting of: 1-nitropropane,nitroethane, and nitromethane; a second component, comprising thebalance of the additive formulation, one or more selected from the groupconsisting of: ester oil modified to remove tricresyl phosphate andtoluene; said additive added to said fuel to a final concentration ofless than about 5 volume percent of said additive in said fuel; theadditive formulation reducing one or more emissions selected from thegroup consisting of: total hydrocarbons, non-methane hydrocarbons,carbon monoxide, NO_(x), and ozone precursors.
 91. The formulation ofclaim 90, wherein said first component comprises: 20 to 40 volumepercent nitromethane, and 60 to 80 volume percent of one or morenitroparaffin components, selected from the group consisting of:1-nitropropane, and nitroethane.
 92. The formulation of claim 90,wherein said first component comprises about 10 to 40 volume percentnitromethane.
 93. The formulation of claim 90, wherein said secondcomponent is ester oil modified to remove tricresyl phosphate andfurther comprising a third component which is toluene.
 94. Theformulation of claim 90, further comprising less than 20 volume percenttoluene and less than 10 volume percent ester oil.
 95. The formulationof claim 90, wherein said formulation is added to said fuel at aconcentration of less than about 0.5 oz. of said formulation per gallonof fuel.
 96. The formulation of claim 90, wherein said formulation isused in an internal combustion engine.
 97. An additive formulation formotor fuels comprising: from about 10 to about 30 volume percentnitromethane; from about 10 to about 30 volume percent nitroethane; fromabout 40 to about 60 volume percent 1-nitropropane; from about 2 toabout 8 volume percent toluene; and from about 1 to about 3 volumepercent modified ester oil, from which substantially all tricresylphosphate has been removed; said additive added to said fuel to a finalconcentration of less than about 5 volume percent of said additive insaid fuel.
 98. The formulation of claim 97, further comprising: about 20volume percent nitromethane, about 20 volume percent nitroethane, andabout 60 volume percent 1-nitropropane.
 99. The formulation of claim 97,further comprising about 10 volume percent toluene and about 2 volumepercent of said modified ester oil.
 100. The formulation of claim 97,wherein said formulation is added to said fuel at a concentration ofless than about 0.5 oz. of said formulation per gallon of fuel.
 101. Theformulation of claim 97, wherein said formulation is used in an internalcombustion engine and reduces emissions of said internal combustionengine.
 102. The formulation of claim 83, 96, or 101, wherein saidinternal combustion engine is selected from the group consisting of: agasoline engine and a diesel engine.
 103. The formulation of claim 83 or101, wherein said reduced emissions comprises a reduction in one or moreemissions selected from the group consisting of: carbon monoxide, totalhydrocarbon, non-methane hydrocarbon, NO_(x), and ozone precursors. 104.The formulation of claim 83, 90, or 97, wherein said ester oil comprisesless than about 2 volume percent of said additive formulation to reduceone or more emissions selected from the group consisting of: exhaustemissions and hydrocarbon emissions.
 105. The formulation of claim 83,90, or 97, wherein the nitroparaffin component comprises less than about10 volume percent of said formulation to reduce the toxicity of saidadditive formulation.
 106. The formulation of claim 83, 90, or 97,wherein the nitroparaffin component comprises more than about 10 volumepercent of said formulation to increase one or more selected from thegroup consisting of: fuel mileage and fuel economy.
 107. An additiveformulation for motor fuels for use in an internal combustion enginecomprising: nitroparaffin; ester oil; and an aromatic hydrocarbon; saidfuel resulting in reduced emissions relative to motor fuel notcontaining said additive when burned in an internal combustion engine.108. The formulation of claim 107 wherein said aromatic hydrocarbon istoluene.
 109. An additive formulation for motor fuels comprising:nitroparaffin at a concentration of less than about 10 volume percent;and ester oil; said fuel resulting in reduced emissions relative tomotor fuel not containing said additive when burned in an internalcombustion engine.
 110. An additive formulation for motor fuelscomprising: nitroparaffin at a concentration of greater than about 90volume percent; and ester oil; said fuel resulting in reduced emissionsrelative to motor fuel not containing said additive when burned in aninternal combustion engine.
 111. An additive formulation for motor fuelscomprising: nitroparaffin substantially free of 2-nitropropane; andester oil; said fuel resulting in reduced emissions relative to motorfuel not containing said additive when burned in an internal combustionengine.
 112. An additive formulation for motor fuels comprising:nitroparaffin; and ester oil at a concentration of less than about 10volume percent; said fuel resulting in reduced emissions relative tomotor fuel not containing said additive when burned in an internalcombustion engine.
 113. An additive formulation for motor fuelscomprising: nitroparaffin comprising about 10 to 40 volume percentnitromethane and wherein said nitroparaffin is substantially free of2-nitropropane; ester oil comprising less than about 2 volume percent ofsaid formulation, wherein said ester oil is substantially free oftricresyl phosphate; and toluene; wherein said additive added to saidfuel to a final concentration of less than about 5 volume percent ofsaid additive in said fuel; and said fuel resulting in reduced emissionsrelative to motor fuel not containing said additive when burned in aninternal combustion engine.
 114. A method of preparing a fuel additiveformulation, comprising: in a mixing vessel; adding about 1 partmodified ester oil from which substantially all tricresyl phosphate hasbeen removed; adding about 5 parts toluene; allowing said ester oil andsaid toluene to stand for 10 minutes at ambient temperature andpressure; adding about 10 parts nitrometane to said ester oil andtoluene mixture; adding about 10 parts nitroethane to said mixture;adding about 29 parts 1-nitropropane to said mixture; aerating saidmixture gently, through a narrow gauge tube at low pressure, and ambienttemperature; storing the additive.
 115. The additive made by the methodof claim
 114. 116. A motor fuel, comprising an additive made by themethod of claim
 114. 117. A motor fuel, comprising an additive made bythe method of claim 114, at a concentration of about 0.1 oz. of additiveper gallon of motor fuel.
 118. A motor fuel for automobiles, comprisingan additive made by the method of claim
 114. 119. A fuel for reducingemissions from a motor vehicle, comprising: formulating an additivecomprising: nitroparaffin substantially free of 2-nitropropane; andester oil; adding said additive to said fuel at a concentration of lessthan about 0.5 oz. of additive per gallon of fuel.
 120. The fuel ofclaim 119, wherein said nitroparaffin further comprises one or morenitroparaffin components, selected from the group consisting of:1-nitropropane, nitroethine, and nitromethane.
 121. The fuel of claim119, further comprising an aromatic hydrocarbon.
 122. The fuel of claim121, wherein said aromatic hydrocarbon is toluene.
 123. A fuel forreducing emissions from a motor vehicle, comprising: formulating anadditive comprising: a first component, comprising 0 to 80 volumepercent of one or more nitroparaffin components, selected from the groupconsisting of: 1-nitropropane, nitroethane, and nitromethane; a secondcomponent, comprising the balance of the additive formulation, one ormore selected from the group consisting of: ester oil modified to removetricresyl phosphate and toluene; wherein said formulation is added tosaid fuel at a concentration of less than about 0.5 oz. of saidformulation per gallon of fuel; and the additive formulation reducingone or more emissions selected from the group consisting of: totalhydrocarbons, non-methane hydrocarbons, carbon monoxide, NO_(x), andozone precursors.
 124. The fuel of claim 123, wherein said firstcomponent further comprises: 20 to 40 volume percent nitromethane, and60 to 80 volume percent of one or more nitroparaffin components selectedfrom the group consisting of: 1-nitropropane, and nitroethane.
 125. Thefuel of claim 123, wherein said first component comprises about 10 to 40volume percent nitromethane.
 126. The fuel of claim 123, wherein saidsecond component is ester oil modified to remove tricresyl phosphate andfurther comprising a third component which is toluene.
 127. The fuel ofclaim 123, further comprising an additive comprising less than 20 volumepercent toluene and less than 10 volume percent ester oil.
 128. The fuelof claim 123, wherein said additive is added to said fuel at aconcentration of less than about 5 volume percent of said additive insaid fuel.
 129. A fuel for reducing emissions from a motor vehicle,comprising: formulating an additive comprising: from about 10 to about30 volume percent nitromethane; from about 10 to about 30 volume percentnitroethane; from about 40 to about 60 volume percent 1-nitropropane;from about 2 to about 8 volume percent toluene; from about 1 to about 3-volume percent modified ester oil, from which substantially alltricresyl phosphate has been removed; and adding said additive to thefuel to a final concentration of less than about 5 volume percent ofsaid additive in said fuel.
 130. The fuel of claim 129, furthercomprising: about 20 volume percent nitromethane, about 20 volumepercent nitroethane, and about 30 volume percent 1-nitropropane. 131.The fuel of claim 129, further comprising about 10 volume percenttoluene and about 2 volume percent modified ester oil havingsubstantially all of the tricresyl phosphate removed.
 132. The fuel ofclaim 129, wherein said additive is added to said fuel at aconcentration of less than about 0.5 oz. of said formulation per gallonof fuel.
 133. The formulation of claim 119, 123, or 129, wherein saidformulation is used in an internal combustion engine.
 134. The fuel ofclaim 133, wherein said internal combustion engine is selected from thegroup consisting of: a gasoline engine and a diesel engine.
 135. Thefuel of claim 119, 123, or 129, wherein said reduced emissions comprisea reduction in one or more emissions selected from the group consistingof: carbon monoxide, NO,, total hydrocarbon, non-methane hydrocarbon,and ozone precursors.
 136. The fuel of claim 119, 123, or 129, whereinsaid ester oil comprises less than about 2 volume percent of saidadditive formulation to reduce one or more emissions selected from thegroup consisting of: exhaust emissions and hydrocarbon emissions. 137.The fuel of claim 119, 123, or 129, wherein said nitroparaffin componentcomprises less than about 10 volume percent of said formulation toreduce the toxicity of said additive formulation.
 138. The fuel of claim119, 123, or 129, wherein said nitroparaffin component comprises morethan about 10 volume percent of said formulation to increase one or moreselected from the group consisting of: fuel mileage and fuel economy.139. A fuel for reducing emissions from a motor vehicle, comprising:formulating an additive comprising: nitroparaffin comprising about 10 to40 volume percent nitromethane; ester oil comprising less than about 2volume percent of said formulation, wherein said ester oil issubstantially free of tricresyl phosphate; and toluene; adding saidadditive to said fuel at a concentration of less than about 5 volumepercent of said additive in said fuel.
 140. A fuel for reducingemissions from a motor vehicle, comprising: Formulating an additivecomprising: nitroparaffin; ester oil; and an aromatic hydrocarbon;adding said fuel at a concentration less than about 5 volume percent ofsaid additive in said fuel.
 141. The fuel of claim 140 wherein saidaromatic hydrocarbon is toluene.
 142. A fuel for reducing emissions froma motor vehicle, comprising: formulating an additive comprising:nitroparaffin at a concentration less than about 10 volume percent; andester oil; adding said fuel at a concentration of less than about 5volume percent of said additive in said fuel.
 143. A fuel for reducingemissions from a motor vehicle, comprising: formulating an additivecomprising: nitroparaffin at a concentration of greater than about 90volume percent; and ester oil; adding said additive to said fuel at aconcentration less than about 5 volume percent of said additive in saidfuel.
 144. A fuel for reducing emissions from a motor vehicle,comprising: formulating an additive comprising: nitroparaffin; and esteroil at a concentration of less than about 10 volume percent; adding saidadditive to said fuel at a concentration of less than about 5 volumepercent of said additive in said fuel.